**Maths Wiz Solutions Class 7 Chapter 1 Knowing Our Numbers**

Welcome to NCTB Solutions. Here with this post we are going to help 7th class students for the Solutions of Maths Wiz Prime Class 7 Math Book, Chapter 1, Knowing Our Numbers. Here students can easily find step by step solutions of all the problems for Knowing Our Numbers, Self Practice 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I, 1J, 1K, 1L and 1M Also here our mathematics teacher’s are solved all the problems with easily understandable methods with proper guidance so that all the students can understand easily. Here in this post students will get chapter 1 solutions. Here in this post all the solutions are based on ICSE latest Syllabus.

**Knowing Our Numbers Self Practice 1A Solution :**

**Question no – (1) **

**Solution : **

**(a) 23,758 in word form,**

= Twenty three thousand seven hundred fifty eight.

**(b) 70,509 in word form,**

= Seventy thousand five hundred nine.

**(c) 86,002 in word form,**

= Eighty six thousand two.

**(d) 90,018 in word form,**

= Ninety thousand Eighteen.

**Question no – (2) **

**Solution : **

**(a) Fourteen thousand seven hundred thirty-six**

TTH |
TH |
H |
T |
O |

1 |
4 |
7 |
3 |
6 |

In Standard form = 14,736

In Expended form = 10000 + 4000 + 700 + 30 + 6

** (b) Twenty thousand nine hundred forty-five**

TTH |
TH |
H |
T |
O |

2 |
0 |
9 |
4 |
5 |

In Standard form = 20,945

In Expended form = 20000 + 900 + 40 + 5

**(c) Eighty-four thousand eighteen**

TTH |
TH |
H |
T |
O |

8 |
4 |
0 |
1 |
8 |

In Standard form = 84,018

In Expanded form = 80000 + 4000 + 10 + 8

**(d) Fifty-five thousand five**

TTH |
TH |
H |
T |
O |

5 | 5 | 0 | 0 | 5 |

In Standard form = 55,005

In Expanded form = 50000 + 5000 + 5

**Question no – (3) **

**Solution : **

**(a) The place value of the coloured digit in 56,718**

There are two digits after 7

So, the place value of 7 is 700.

**(b) The place value of the coloured digit in 34,650**

There are four digits after 3

So, the place value of 3 is 30000

**(c) The place value of the coloured digit in 89,206**

There are three digits after 9

So, the place value of 9 is 900

**(d) The place value of the coloured digit in 90,632**

There are only one digit after 3

Therefore, the place value of 3 is 30.

**Knowing Our Numbers Self Practice 1B Solution :**

**Question no – (1) **

**Solution : **

**(a) The successor of 9,320**

= 9320 + 1

= 9321

Thus, the successor of 9,320 is 9321.

**(b) The successor of 75,439**

= 75439 + 1

= 75,440

Hence, the successor of 75,439 is 75,440.

**(c) The successor of 80,999**

= 80,999

= 80999 + 1

= 81,000

So, the successor of 80,999 is 81,000.

**(d) The successor of 54,099**

= 54,099

= 54099 + 1

= 54,100

Thus, the successor of 54,099 is 54,100.

**Question no – (2) **

**Solution : **

**(a) The predecessor of 6,548**

= 6,548

= 6548 – 1

= 6547

Thus, the predecessor of 6,548 is 6547.

**(b) The predecessor of 27,235**

= 27,235

= 27235 – 1

= 27,234

So, the predecessor of 27,235 is 27,234.

**(c) The predecessor of 49,700**

= 49,700

= 49,700 – 1

= 49,699

Thus, the predecessor of 49,700 is 49,699

**(d) The predecessor of 85,030**

= 85,030

= 85,030 – 1

= 85,029

Therefore, the predecessor of 85,030 is 85029.

**Question no – (3) **

**Solution : **

**(a)** 9,120 and 19,417

= 9,120 **<** 19,417

**(b)** 7,986 and 10,245

= 7,986 **<** 10,245

**(c)** 54,738 and 64,520

= 54,738 **<** 64,520

**(d)** 15,739 and 15,739

= 15739 **=** 15739

**(e)** 80,615 and 78,976

= 80,615 **>** 78,976

**(f)** 24,865 and 23,938

= 24,865** >** 23,938

**(g)** 61,798 and 61,630

= 61,798 **>** 61,630

**(h)** 26,718 and 26,702

= 26,718 **>** 26,702

**(i)** 20,019 and 20,019

= 20019 **=** 20019

**(j)** 43,597 and 43,599

= 43,597 **<** 43,599

**Knowing Our Numbers Self Practice 1C Solution :**

**Question no – (2) **

**Solution : **

The numeral which represents the greatest number is **(c)** 84,598

**Question no – (3) **

**Solution : **

The numeral which represents the smallest number is **(d)** 18,953

**Question no – (4) **

**Solution : **

**(a)** Given in the question,

90,725; 72,590; 52,709; 25,097; 98,061; 27,950

Now, in ascending order

= 25,097 < 27,950 < 52,709 < 72,590 < 90,725 < 98,061

**(b) **Given numbers are,

15,005; 15,015; 15,505; 15,051; 15,550; 15,150

Now, in ascending order

= 15,005 < 15,015 < 15,051 < 15,150 < 15,505 < 15,550

**Question no – (5) **

**Solution : **

**(a) Given numbers are,**

= 19,284; 48,375; 25,795; 65,722; 83,567; 83,765

Now, in descending order :

= 83,765 > 83,567 > 65,722 > 48,375 > 25,795 > 19,284

**(b) Given numbers are,**

= 24,569; 24,659; 24,596; 24,645; 24,605; 24,650

Now, in descending order :

= 24,659 > 24,650 > 24,645 > 24,605 > 24,596 > 24,569.

**Question no – (5) **

**Solution : **

Assam 78,438 > Meghalaya 22,429 > Manipur 22,327 > Mizoram 21,081 > Nagaland 16,579 > Tripura 10,486

**Knowing Our Numbers Self Practice 1D Solution :**

**Question no – (1) **

**Solution : **

**(a) Given, 2, 4, 6**

Possible 3-digit numbers = 246, 426, 642, 264, 462, 624

**(b) 7, 3, 9**

Possible 3-digit numbers = 739, 379, 937, 793, 397, 973

**(c) 8, 0, 1**

Possible 3-digit numbers = 801, 108, 810, 180

**(d) 0, 6, 9**

Possible 3-digit numbers = 609, 906, 690, 960

**Question no – (2) **

**Solution : **

**(a) Given numbers, 5, 3, 7, 4**

Smallest number = 3457,

Greatest number = 7543

**(b) 8, 3, 4, 9**

Smallest number = 3489,

Greatest number = 9843

**(c) 6, 0, 9, 7**

Smallest number = 6079,

Greatest number = 9760

**(d) 4, 0, 8, 0**

Smallest number = 4008

Greatest number = 8400

**(e) 2, 6, 9, 1, 7**

Smallest number = 12679

Greatest number = 97621

**(f) 3, 6, 0, 5, 8**

Smallest number 30568,

Greatest number = 86530

**(g) 8, 9, 0, 2, 0**

Smallest number = 20089,

Greatest number = 98200

**(h) 3, 5, 3, 2, 0**

Smallest number = 20335,

Greatest number = 53320

**Knowing Our Numbers Self Practice 1E Solution :**

**Question no – (1) **

**Solution : **

**(a) **The the nearest ten of 57 is **60.**

Because, 57 is between of 50 and 60.

**(b)** The nearest ten of 84 is **80**

**(c) **Rounding off 935 to the nearest ten is **940.**

Because, 935 is between of 930 and 940.

**(d) **The nearest ten of 869 is **870.**

Because, 869 is between of 860 and 870

**(e) **The nearest ten of 4539 is **4540.**

**(f)** The nearest ten of 8894 is **8890**

**(g)** The nearest ten of 6397 is **6400**

**(h) **Rounding off 82035 to the nearest ten is **82040.**

Because, 82035 is between of 82030 and 82040.

**(i)** The nearest ten of 71,298 is **71,300.**

**(j)** The nearest ten of 20193 is **20190.**

**Question no – (2) **

**Solution :**

**(a)** Rounding off 624 to the nearest hundred is **600**

**(b) **The nearest hundred of 136 is **100**

**(c) **The nearest hundred of 2095 is **2100**

Because, 2095 is between of 2090 and 2100

**(d)** The nearest hundred of 4053 is **4100**

**(e)** The nearest hundred of 5974 is **6000**

**(f)** Rounding off to the nearest hundred of 20,809 is **28,800**

**(g) **The nearest hundred of 18,994 is **19,000.**

**(h)** The nearest hundred of 79,992 is **80,000**

**(i) **The nearest hundred of 69,925 is **69,000.**

**(j)** The nearest hundred of 12950 is **13000**

**Question no – (3) **

**Solution : **

**(a)** The nearest thousand of 3725 is **4000**

**(b)** The nearest thousand of 6498 is **6000**

**(c) **The nearest thousand 9516 is **10000.**

Because, 9516 is between of 9000 and 1000

**(d)** The nearest thousand of 5946 is **6000**

**(e) **The nearest thousand of 21586 is **22000**

Because 21586 is between of 21000 and 22000.

**(f)** The nearest thousand of 69,927 is **70,000**

**(g)** The nearest thousand of 80,279 is **80,000**

**(h) **The nearest thousand of 25,806 is **2600**

Because 25,806 is between of 25000 and 26000.

**(i)** The nearest thousand 79,634 is **80,000**

**(j) **The nearest thousand of 40,389 is **40,000**

**Knowing Our Numbers Self Practice 1F Solution :**

**Question no – (1) **

**Solution : **

**(a) 68 + 53**

= 68 rounded off to the nearest ten = 70

= 53 rounded off to the nearest ten = 50

**∴** 70 + 50

= 120

Thus, the sum will be 120.

**(b) 466+ 325**

= 466 rounded off to the nearest hundred = 400

= 325 rounded off to the nearest hundred = 400

**∴** 400 + 400

= 800

Thus, the sum will be 800.

**(c) 8,379 + 264**

= 8379 rounded off to the nearest thousand = 8400

= 264 rounded off to the nearest thousand = 300

**∴** 8400 + 300

= 8700

Therefore, the sum will be 8700

**(d) 1,693 + 4,509**

= 1693 = rounded off to the nearest thousand = 1700

= 4509 = rounded off to the nearest thousand = 4500

**∴** 1700 + 4500 = 6200

Therefore, the sum will be 6200.

**(e) 27,619 + 53,987**

= 27619 = rounded off to the nearest thousand = 30,000

= 53,987 = rounded off to the nearest thousand = 50,000

**∴** 30,000 + 50,000 = 80,000

Thus, the sum will be 80,000.

**Question no – (2) **

**Solution : **

**(a) 898 – 345**

= 898 rounded off to the nearest hundred = 900

= 345 rounded off to the nearest hundred = 300

**∴** 900 – 300

= 600.

Hence, the difference will be 600.

**(b) 839 – 48**

= 839 rounded off to the nearest hundred = 840

= 48 rounded off to the nearest hundred = 50

**∴** 840 – 50

= 790

Thus, the difference will be 790.

**(c) 362 – 279**

= 362 rounded off to the nearest hundred = 350

= 279 rounded off to the nearest hundred = 250

**∴** 300 – 250

= 100

So, the difference will be 100.

**(d) 5,718 – 2,014**

= 5718 rounded off to the nearest hundred = 6000

= 2014 rounded off to the nearest hundred = 2000

**∴** 6000 – 2000 = 4000

Hence, the difference will be 4000.

**(e) 73,284 – 39,541**

= 73284 rounded off to the nearest hundred = 70000

= 39541 rounded off to the nearest hundred = 40000

**∴** 70000 – 40000

= 30,000

Therefore, difference will be 30,000.

**Question no – (3) **

**Solution : **

**(a) 68 × 7**

= 68 rounded off to the nearest ten = 70

= 70 × 7

= 490

Thus, the product will be 490

**(b) 523 × 16**

523 rounded off to the nearest hundred = 500

16 rounded off to the nearest ten = 20

**∴** 500 × 20

= 10,000

Hence, the product will be 10,000.

**(c) 517 × 68**

517 rounded off to the nearest hundred = 500

68 rounded off to the nearest ten = 70

**∴** 500 × 70

= 35,000

Thus, the product will be 35,000.

**(d) 74 × 87**

74 rounded off to the nearest ten = 70

87 rounded off to the nearest ten = 90

**∴** 70 × 90

= 6300

Hence, the product will be 6300.

**(e) 408 × 189**

408 rounded off to the nearest hundred = 400

189 rounded off to the nearest hundred = 200

**∴** 400 × 200

= 80,000

Thus, the product will be 80,000.

**Question no – (4) **

**Solution : **

**(a) 123 ÷ 8**

123 rounded off to the nearest ten = 120

**∴** 120 ÷ 8

= 15

Therefore, the quotient will be 15.

**(b) 157 ÷ 19**

157 rounded off to the nearest ten = 160

19 rounded off to the nearest ten = 20

**∴** 160 ÷ 20

= 8

Hence, the quotient will be 8.

**(c) 958 ÷ 49**

958 rounded off to the nearest hundred = 1000

49 rounded off to the nearest ten = 50

**∴** 1000 ÷ 50

= 20

Therefore, the quotient will be 20.

**(d) 7,982 ÷ 1,728**

7,982 rounded off to the nearest thousand = 8000

1,728 rounded off to the nearest thousand = 2000

∴ 8000 ÷ 2000

= 4

Thus, the quotient will be 4.

**(e) 17,869 ÷ 8,759**

17,869 rounded off to the nearest ten thousand = 20000

8,759 rounded off to the nearest ten thousand = 1000

**∴** 20000 ÷ 10000

= 2

Therefore, the quotient will be 2.

**Question no – (5) **

**Solution : **

**(a) 7,680 + 4,293; thousands**

= 7680 rounded off to the nearest thousand = 8000

= 4293 rounded off to the nearest thousand = 4000

**∴** 8000 + 4000

= 12000

**(b) 58,734 – 14,695; ten thousands**

= 58,734 rounded off to the nearest thousand = 60,000

= 14,695 rounded off to the nearest thousand = 10,000

**∴** 60,000 – 10,000

= 50,000

**Knowing Our Numbers Self Practice 1G Solution :**

**Question no – (1) **

**Solution : **

**(a) 536218 in word form,**

= 536218 = Five lakh thirty six thousand two hundred eighteen.

**(b) 290314 in word form,**

= 290314 = Two lakh three hundred fourteen.

**(c) 2738546 in word form,**

= 2738546 = Twenty seven lakh thirty eight thousand five hundred forty six.

**(d) 8219360 in word form,**

= 8219360 = Eighty two lakh nineteen thousand three hundred sixty

**(e) 6050007 in word form,**

= 6050007 = Sixty lakh fifty thousand seven.

**(f) 7802100 in word form,**

= 7802100 = Seventy eight lakh two thousand one hundred.

**(g) 5008019 in word form,**

= 5008019 = Fifty lakh eight thousand nineteen.

**(h) 9000005 in word form,**

= 9000005 = Ninety lakh five.

**(i) 35286174 in word form**

= 35286174 = Three crore fifty two lakh eighty six thousand one hundred seventy four.

**(j) 91654278 in word form,**

= 91654278 = Nine crore sixteen lakh fifty four thousand two hundred seventy eight.

**(k) 80512009 in word form**

= 80512009 = Eight crore five lakh Twelve thousand nine.

**(l) 50037504 in word form**

= 50037504 = Five crore thirty seven thousand five hundred four.

**(m) 60702040 in word form**

= 60702040 = Six crore seventy lakh two thousand forty.

**(n) 10000009 in word form**

= 10000009 = One crore nine.

**(o) 70209030 in word form**

= 70209030 = Seven crore twenty lakh Nine thousand thirty.

**(p) 10001001 in word form**

= 10001001 = One crore One thousand one.

**Question no – (2) **

**Solution : **

**(a)** Four lakh seventy five thousand two hundred fifteen

In standard form = 4,75,215

**(b)** Seven lakh two thousand one hundred

In standard form = 7,02,100

**(c)** Twelve lakh fifty thousand eight hundred four

In standard form = 12,50,804

**(d)** Twenty lakh seven hundred

In standard form = 20,00,700

**(e)** Two crore seventy-four lakh forty-five thousand three hundred forty-five

In standard form = 2,24,45,345

**(f) **Seven crore thirty-one lakh five thousand eight hundred nine

In standard form = 7,31,05,809

**(g)** Five crore sixty thousand

In standard form = 5,00,60,00

**(h)** Three crore seven thousand eighteen

In standard form = 3,00,07,018

**Knowing Our Numbers Self Practice 1H Solution :**

**Question no – (1) **

**Solution : **

**(a) Given, 58,397**

∴ Place value of 8,

= 8 × 1000 [∵ we get three digit after 8]

= 8000

Thus, the pace value of 8 will be 8000.

**(b) 9,83,721**

∴ Place value of 8,

8 = 8 × 10000 [∵ we get four digit after 8]

= 80000

Hence, the place value of 8 will be 80000.

**(c) 48,59,326**

∴ Place value of 8,

8 = 8 × 100000 [∵ we get five digit after 8]

= 8,00,000

Thus, the place value of 8 will be 8,00,000.

**(d) 83,70,925**

∴ Place value of 8,

8 = 8 × 1000000 [∵ we get six digit after 8]

= 80,00,000

Therefore, the place value of 8 will be 80,00,000.

**(e) 8,73,21,009**

∴ Place value of 8,

8 = 8 × 10000000 [∵ we get seven digit after 8]

= 800,00,000

Thus, the place value of 8 will be 800,00,000.

**(f) 6,90,57,812**

∴ Place value of 8,

8 = 8 × 100 [∵ we get two digit after 8]

= 800

Therefore, the place value of 8 will be 800.

**Question no – (2) **

**Solution : **

**(a)** Given, 29,75,384

**∴**** Place value of 4**

= 4 × 1

= 4

**∴**** Place value of 8**

= 8 × 10

= 80

**∴**** Place value of 3**

= 3 × 100

= 300

**∴**** Place value of 5**

= 5 × 1000

= 5000

**∴**** Place value of 7**

= 7 × 100000

= 700000

**∴**** Place value of 9**

= 9 × 100000

= 900000

**(b) Given number, 6,72,35489**

∴ Place value of 9

= 9 × 1

= 9

**∴**** Place value of 8**

= 8 × 10

= 80

**∴**** Place value of 4**

= 4 × 100

= 400

**∴**** Place value of 5**

= 5 × 5000

= 5000

**∴**** Place value of 3**

= 3 × 10000

= 30000

**∴**** Place value of 2**

= 2 × 100000

= 200000

**∴**** Place value of 7**

= 7 × 1000000

= 7000000

**∴**** Place value of 6**

= 6 × 10000000

= 60000000

**Question no – (3) **

**Solution : **

**(a) 725964**

In place value chart :

C | TL | L | TTH | TH | H | T | O |

7 | 2 | 5 | 9 | 6 | 4 |

In expanded form :

725964 = 700000 + 20000 + 5000 + 900 + 60 + 4

**(b) 2649837**

In place value chart :

C | TL | L | TTH | TH | H | T | O |

2 | 6 | 4 | 9 | 8 | 3 | 7 |

In expanded form :

2649837 = 2000000 + 600000 + 40000 + 9000 + 800 + 30 + 7

**(c) 50960714**

In place value chart :

C | TL | L | TTH | TH | H | T | O |

5 | 0 | 9 | 6 | 0 | 7 | 1 | 4 |

In expanded form :

50960714 = 50000000 + 900000 + 60000 + 700 + 10 + 4

**Knowing Our Numbers Self Practice 1J Solution : **

**Question no – (1) **

**Solution : **

As per the given question,

First year = 25,750 km

Second year = 20,675 km

Third year = 23,928 km

**∴ **He rode in 3 years,

= (25750 + 20675 + 23928)

= 70353 km

Hence, Rahul rode his motorbike 70353 km in the 3 years.

**Question no – (2) **

**Solution : **

She deposited Rs 8,24, Rs 19,766 and Rs 15,238

**∴ **Final balance,

= 10, 000 + 8, 425 + 19, 766 + 15,238

= 53, 429

Thus, the final balance in her account will be 53,429 Rs.

**Question no – (3) **

**Solution : **

According to the question,

Gratuity of = ₹ 18, 60, 750

Bought a car for = ₹325,000

Invested in mutual funds = ₹2,70,000

**∴ **He put in fixed deposit,

= 18, 60, 750 – (3, 25000 + 2, 70,000)

= 12, 65, 750

Therefore, he put Rs. 12, 65, 750 in fixed deposit.

**Question no – (4) **

**Solution : **

From the question we get,

Total population = 9, 12, 76, 115

Male = 46809, 027

**∴ **Female,

= (9, 1276115 – 44809027)

= 4, 4467, 088

**∴ **Expended form

= 40000000 + 4000000 + 400000 + 60000 + 7000 + 80 + 8

**∴ **Word form

= Four crore forty four lakh sixty seven thousand eighty eight.

**Question no – (5) **

**Solution :**

As per the given question,

Cricket players = 20

Award money, each get = Rs 8, 75, 000

**∴ **Total money awarded,

= 875000 × 20

= 17,50, 0000

Therefore, the total amount of money awarded is 17,50, 0000 Rs.

**Question no – (6) **

**Solution :**

As per the given question,

Builder sold = 16 flats

Price of each flat = Rs 55, 66, 800

**∴ **Total money receive in all from the sale

= 5566800 × 16

= 8, 90, 68,800

Therefore, he receive Rs, 8, 90, 68,800 in all from this sale.

**Question no – (7) **

**Solution :**

As per the question we know,

Amount = Rs 9, 15,750

Shared equally = 185 people

**∴** Each person receive,

= 915750/185

= 4950

Therefore, each person receive 4950 Rs.

**Question no – (8) **

**Solution :**

As per the given question,

Company’s yearly profit = Nine crore (90000000)

Shareholders = 500

**∴** Each shareholders will received,

= 900, 00,000/500

= 18, 0000

Therefore, each shareholder receive 18, 0000 Rs.

**Question no – (9) **

**Solution : **

According to the question,

Total soup quantity = 15 L = 15000 mL

Each bowl serves = 400 mL

**∴** 28 each bowl serves,

= 400 × 28

= 11,200 mL

**∴** Soup will left,

= 15000 – 11200

= 3800 mL

Therefore, 3800 mL soup is left in the pot.

**Question no – (10) **

**Solution : **

Given, Length = 1 m 70 cm

= (1 × 100) + 70….(Metre to Centimeter)

= 170 cm

Breadth = 90 cm

**∴** Perimeter of frame,

= 2 (170 + 90)

= 2 × 260

= 520 cm

**∴** Wood will need,

= 520 – 500

= 20 cm

Therefore, Anushka have not enough wood to frame the picture.

**Question no – (11) **

**Solution : **

As per the question we know,

Rice consumed daily by students = 56 kg = 5600g

Each student consume = 35g

**∴** Number of student,

= 5600/35

= 1600

Therefore, the number of students in the school are 1600.

**Question no – (12) **

**Solution : **

According to the question,

Tablet contains is a box = 2, 50, 700

Weight of each tablet = 15 mg.

**∴** Weight of all tablet,

**=** (250700 × 15)

= 3760500 mg

= 3760500/1000000

= 3.760500 kg

Therefore, the total weight of all the tablets will be 3.760500 kg.

**Question no – (13) **

**Solution : **

Australia has a coastline = 25,760 km

Canada has a coastline = 2, 02, 080 km

**∴** Longest coastline of them,

= 202080 – 25760

= 176, 320 km.

Thus, Canada has a longer coastline by 176, 320 km.

**Question no – (14) **

**Solution : **

Weight of 80 packet biscuit,

= 125 × 80

= 10000 gm.

= 10000/1000 = 10 kg

Maximum load = 800 kg.

**∴** Van can carry,

= 800/10

= 80 box

Therefore, 80 boxes can be loaded in the van.

**Question no – (15) **

**Solution : **

State in descending order according to their population,

(i) West Bengal. (9, 12, 76, 115)

⬇

(ii) Tamil Nadu. (7, 21, 47, 030)

⬇

(iii) Rajasthan. (6, 85, 48, 437)

⬇

(iv) Karnataka. (3, 09, 66, 657)

Or,

**(i)** → **(ii)** → **(iii)** → **(iv)**

**Knowing Our Numbers Self Practice 1K Solution : **

**Question no – (1) **

**Solution : **

**(a) 4, 863, 000**

= Four million eight hundred sixty three thousand.

**(b) 56, 317, 900**

= Fifty six million three hundred seventeen thousand nine hundred.

**(c) 8, 406, 008**

= Eight million four hundred six thousand eight.

**(d) 75, 219, 038**

= seventy five million two hundred nineteen thousand thirty eight.

**(e) 92, 594, 168**

= Ninety two million five hundred ninety four thousand one hundred sixty eight.

**(f) 50,000,003**

= Fifty million three.

**Question no – (2) **

**Solution : **

**(a)** 5390721 = 5, 390, 721

**(b)** 69345071 = 69, 345, 071

**(c)** 80374629 = 80, 374, 629

**(d)** 2003798 = 2, 003, 798

**(e)** 79035 = 792, 035

**(f)** 87200965 = 87, 200, 965

**Question no – (3) **

**Solution : **

**(a) Three hundred fifty-seven thousand two hundred nineteen**

= 357219

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

3 | 5 | 7 | 2 | 1 | 9 |

**(b) Four million ne hundred seventy thousand fifty-five**

= 4, 170, 55

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

4 | 1 | 7 | 0 | 0 | 5 | 5 |

**(c) Sixty-seven million nine hundred thousand four hundred ninety-one**

= 67,900,491

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

6 | 7 | 9 | 0 | 0 | 4 | 9 | 1 |

**(d) Nine million one hundred nine thousand seven hundred five**

= 9, 109, 705

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

9 | 1 | 0 | 9 | 7 | 0 | 5 |

**(e) Seven hundred thousand**

= 700, 000

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

7 | 0 | 0 | 0 | 0 | 0 |

**(f) Fifty-eight million**

= 58, 000, 000

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

5 | 8 | 0 | 0 | 0 | 0 | 0 | 0 |

**(g) Six million five hundred thousand seven**

= 6, 500, 007

In place value chart :

TM | M | HTH | TTH | TH | H | T | O |

6 | 5 | 0 | 0 | 0 | 0 | 7 |

**Question no – (4) **

**Solution : **

**(a)** 5 × 100, 000 + 7 × 10,000 + 8 × 1,000 + 3 × 100 + 9 × 10 + 2

In standard form = 578, 392

**(b)** 7 × 1, 000,000 + 4 × 100, 000 + 4 × 10, 000 + 5 × 1, 000 + 3 × 100 + 8 × 10 + 6 × 1

In standard form = 7, 445, 386

**(c)** 8 × 10, 000, 000 + 3 × 1, 000, 000 + 7 × 100, 000 + 5 × 10, 000 + 2 × 1, 000 + 9 × 100 + 1 × 10 + 6

In standard form = 83, 752, 916

**Question no – (5) **

**Solution : **

**(a)** **735, 448**

In expanded form : 7 × 100, 000 + 3 × 10, 000 + 5 × 1,000 + 4 × 10 + 8

**(b) 2, 634, 789**

In expanded form : 2 × 100, 000 + 6 × 100, 000 + 3 × 10, 000 + 4 × 1,000 + 7 × 100 + 8 × 10 + 9

**(c) 9, 050, 254**

In expanded form : 9 × 1000, 000 + 5 × 10, 000 + 2 × 100 + 5 × 10 + 4]

**Knowing Our Numbers Self Practice 1L Solution : **

**Question no – (1) **

**Solution : **

**(a) Roman numeral of 14,**

14 = 10 + (5 – 1)

And we know,

X = 10; IV = 4

**∴** 14 = XIV

**(b) Roman numeral of 21,**

21 = 10 + 10 + 1

And we know,

X = 10; X = 10; I = 1

**∴** 21 = XXI

**(c) Roman numeral of 39,**

39 = 10 + 10 + 10 + (10 – 1)

And we know,

X = 10; X = 10; X = 10; IX = 9

**∴** 39 = XXXIX

**(d) Roman numeral of 45,**

45 = (50 – 10) + 5

And we know,

XL = 40; V = 5

**∴** 45 = XLV

**(e) Roman numeral of 65,**

65 = (60 + 5)

And we know,

LX = 60; V = 5

**∴** 65 = LXV

**(f) Roman numeral of 86,**

86 = 80 + 5 + 1

And we know,

LXXX = 80; V = 5; I = 1

**∴** 86 = LXXXVI

**(g) Roman numeral of 96**

96 = 90 + 5 + 1

And we know,

XC = 90; V = 5; I = 1

**∴** 96 = XCVI

**(h) Roman numeral of 128,**

128 = 100 + 20 + (10 – 20)

And we know,

C = 100, XX = 20, VIII = 8

**∴** CXXVIII = 128

**(i) Roman numeral of 352,**

352 = 100 + 100 + 100 + 50 + 2

And we know,

C = 100; C = 100; C = 100; L = 50; II = 2

**∴** 352 = CCCLII

**(j) Roman numeral of 635,**

635 = 100 + 100 + 100 + 100 + 100 + 100 + 10 + 10 + 10 + 5

And we know,

C = 100; C = 100; C = 100; C = 100; C = 100; C = 100; XXX = 30; V = 5

**∴** 635 = CCCCCCXXXV

**Question no – (2) **

**Solution : **

**(a) Hindu-Arabic numeral of XLVI,**

We know,

XLVI = XL = 40; V = 5; I = 1

**∴** 40 + 5 + 1 = 46

**∴** XLVI = 46

**(b) Hindu-Arabic numeral of LXXVIII,**

We know,

LXXVIII = LX = 60; X = 10; V = 5; III = 3

**∴** 60 + 10 + 5 + 3 = 78

**∴** LXXVIII = 78

**(c) Hindu-Arabic numeral of XXXIV,**

We know,

XXXIV = X = 10; X = 10; X = 10; IV =4

**∴** 30 + 4 = 34

**∴** XXXIV = 34

**(d) Hindu-Arabic numeral of LIX,**

We know,

LIX = L = 50; IX = 9

**∴** 50 + 9 = 59

**∴** LIX = 59

**(e) Hindu-Arabic numeral of LXVI ,**

We know,

LXVI = LX = 60; V = 5; I = 1

**∴** 60 + 5 + 1 = 66

**∴** LXVI = 66

**(f) Hindu-Arabic numeral of CCCXLV,**

We know,

CCCXLV = C = 100; C = 100; C = 100; XL = 40 V = 5

**∴** 100 + 100 + 100 + 40 + 5 = 345

**∴** CCCXLV = 345

**(g) Hindu-Arabic numeral of CLXXIII,**

We know,

CLXXIII = C = 100; LXX = 70; III = 3

**∴** 100 + 70 + 3 = 173

**∴** CLXXIII = 173

**(h) Hindu-Arabic numeral of CCXXX,**

We know,

CCXXX= C = 100; C = 100; X = 10; X = 10; X = 10;

**∴** 100 + 100 + 10 + 10 + 10 = 230

**∴** CCXXX= 230

**(i) Hindu-Arabic numeral of DCCIX,**

We know,

DCCIX = D = 500; C = 100; C = 100; IX = 9

**∴** 500 + 200 + 9 = 709

**∴** DCCIX = 709

**(j) Hindu-Arabic numeral of CDXXI,**

We know,

CDXXI = CD = 400; XX = 20; I = 1

**∴** (500 – 100) + 20 + 1 = 400 + 20 + 1 = 421

**∴** CDXXI= 421

**Knowing Our Numbers Self Practice 1M Solution : **

**Question no – (1) **

**Solution :**

Given, 6 + (2 × 5)

= 6 + 10

= 16

**Question no – (2) **

**Solution :**

Given, (6 + 4) × 5

= 20 × 5

= 100

**Question no – (3) **

**Solution :**

Given, 3 + (6 + 8)

= 3 + 14

= 17

**Question no – (4) **

**Solution :**

Given, (10 – 3) + 13

= 7 + 13

= 20

**Question no – (5) **

**Solution :**

Given, 18 – (3 + 7)

= 18 – 10

= 8

**Question no – (6) **

**Solution :**

Given, (8 × 15) – 20

= 120 – 20

= 100

**Question no – (7) **

**Solution :**

Given, 27 – (6 × 4)

= 27 – 24

= 3

**Question no – (8) **

**Solution :**

Given, 30 – (112 ÷ 14)

= 30 – 28

= 2

**Question no – (9) **

**Solution :**

Given, (35 – 15) ÷ 4

= 20 ÷ 4

= 5

**Question no – (10) **

**Solution :**

Given, 80 ÷ (5 × 4)

= 80 ÷ 20

= 4

**Next Chapter Solution : **

👉 Chapter 2 👈