# Maths Wiz Solutions Class 7 Chapter 6

## Maths Wiz Solutions Class 7 Chapter 6 Decimals

Welcome to NCTB Solutions. Here with this post we are going to help 7th class students for the Solutions of Maths Wiz Class 7 Math Book, Chapter 6, Decimals. Here students can easily find step by step solutions of all the problems for Decimals, Self Practice 6A, 6B, 6C, 6D, 6E, 6F, 6G, 6H, 6I, 6J and 6K 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 6 solutions. Here in this post all the solutions are based on ICSE latest Syllabus.

Decimals Self Practice 6A Solution :

Question no – (1)

Solution :

Here is the required Place value table :

 Hundred Tens Ones Tenths hundred Thousandths (a) 0 . 4 (b) 0 . 0 7 (c) 0 . 5 8 (d) 0 . 2 3 (e) 0 . 9 0 4 (f) 0 . 3 (g) 4 5 . 0 7 (h) 1 6 9 . 0 6 7 (i) 0 . 8 7 6 (j) 7 8 . 3 0 2 (k) 6 3 2 . 0 0 1

Question no – (2)

Solution :

(a) The place value of 7 in 0.17

= 7/100 or 0.07

(b) The place value of 7 in 7.52,

= 7 ones or 7

(c) The place value of 7 in 0.735

= 7/10 or 0/7

(d) The place value of 7 in 2.357

= 7/1000

(e) The place value of 7 in 79.43,

= 7 tens or 70

Question no – (3)

Solution :

(a) The place value of 3 in 0.583

= 3 thousandths

= 3/1000

= 0.003

(b) The place value of 3 in 0.358

= 3 tenths

= 3/10

= 0.3

(c) The place value of 3 in 0.538

= 3 hundredths

= 3/1000

= 0.003

(d) The place value of 3 in 3.097

= 3 ones

(e) The place value of 3 in 37.004

= 3 tens or 30

Decimals Self Practice 6B Solution :

Question no – (1)

Solution :

(a) 6 tenths in standard form = 0.6

(b) 23 and 8 tenths in standard form = 23.8

(c) 8 hundredths in standard form = 0.08

(d) 9 + 0.04 in standard form = 9.04

(e) 42 and 87 thousandths in standard form = 42.087

(f) 1 ten thousandths in standard form = 0.0001

(g) 19 and 62 hundredths in standard form = 19.62

(h) 598 ten thousandths in standard form = 0.0598

Question no – (2)

Solution :

(a) 1/10 + 9/100 in standard form,

∴ 1/10 + 9/100

= 0.1 + 0.09

= 0.19 …(Standard form)

(b) 5/10 + 2/100 + 9/1000 in standard form,

∴ 5/10 + 2/100 + 9/1000

= 0.5 + 0.02 + 0.009

= 0.529  …(Standard form)

(c) 40 + 8 + 6/10 + 3/100 in standard form,

∴ 40 + 8 + 6/10 + 3/100

= 40 + 8 + 0.6 + 0.03

= 48.63  …(Standard form)

(d) 700 + 4 + 3/10 + 7/100 in standard form,

∴ 700 + 4 + 3/10 + 7/100

= 700 + 4 + 0.3 + 0.07

= 704.37    …(Standard form)

(e) 8 + 3/100 in standard form,

8 + 3/100

= 8 + 0.03

= 8.03    …(Standard form)

(f) 6/10 + 8/1000 in standard form,

6/10 + 8/1000

= 0.6 + 0.008

= 0.608

Hence, standard form of 6/10 + 8/1000 is 0.608

(g) 1/10 + 8/1000 + 3/10000 in standard form,

1/10 + 8/1000 + 3/10000

= 0.1083   …(Standard form)

(h) 9 + 0.3 + 0.07 + 0.009 in standard form,

9 + 0.3 + 0.07 + 0.009

= 9.379   …(Standard form)

(i) 0.3 + 0.005 + 0.0007 in standard form,

0.3 + 0.005 + 0.0007

= 0.3057

Thus, standard form of 0.3 + 0.005 + 0.0007 is 0.3057

(j) 500 + 60 + 8 + 0.06 + 0.002 in standard form,

500 + 60 + 8 + 0.06 + 0.002

= 568.062

So, standard form of 500 + 60 + 8 + 0.06 + 0.002 is 568.062

Question no – (3)

Solution :

(a) 0.3 in expanded form

= 3/10

(b) 4.7 in expanded form

= 4 + 7/10

(c) 4.78 in expanded form

= 4 + 7/10 + 8/100

(d) 0.96 in expanded form

= 9/10 + 6/100

(e) 0.215 in expanded form

= 2/10 + 1/100 + 5/1000

(f) 6.149 in expanded form

= 6 + 1/10 + 4/100 + 9/1000

(g) 49.06 in expanded form

= 40 + 9 + 6/100

(h) 947.068 in expanded form

= 900 + 40 + 7 + 6/100 + 8/1000

Decimals Self Practice 6C Solution :

Question no – (1)

Solution :

(a) 0.7 in words

= Zero point seven.

(b) 0.89 in words

= Zero point eight nine.

(c) 7.38 in words

= Seven point three eight

(d) 0.04 in words

= Zero point Zero four

(e) 94.075 in words

= Ninety four point zero seven five

(f) 0.009 in words

= Zero points zero zero nine

(g) 8.0033 in words

= Eight point zero zero three two

(h) 735.19 in words

= Seven hundred thirty five point one nine.

Question no – (2)

Solution :

(a) Zero point eight in numerals

= 0.8

(b) Zero point five nine in numerals

= 0.59

(c) Point zero two one seven in numerals

= 0.0217

(d) Fifty-four point zero nine in numerals

= 54.09

(e) Two hundred nine point zero zero three in numerals

= 209.003

(f) Eight and five tenths in numerals

= 8.5

(g) Seventeen and four hundredths in numerals

= 17.04

(h) Seventy-nine and fifty-two thousandths in numerals

= 79.052

Decimals Self Practice 6D Solution :

Question no – (1)

Solution :

(a) 6.348

= The number of decimal places is 3

(b) 0.4

= The number of decimal places is 1

(c) 22.7813

= The number of decimal places is 4

(d) 7.0029

= The number of decimal places is 4

Question no – (2)

Solution :

(a) 4.01, 6.7, 24.352, 0.023 – in like decimal,

= 4.010, 6.700, 24.352, 0.023

(b) 1.8, 0.6, 3.97, 29.015– in like decimal,

= 1.800, 0.600, 3.970, 29.015

Question no – (3)

Solution :

(a) 6.29 < 7.58

(b) 29.13 19.86

(c) 0.4 < 0.6

(d) 0.49 < 1

(e) 0.8 = 0.80

(f) 1.405 < 1.45

(g) 0.31 > 0.103

(h) 0.98 < 1

(i) 0.72 > 0.702

(j) 0.84 > 0.084

(k) 0.07 = 0.070

(l) 0.08 < 0.8001

Question no – (4)

Solution :

(a) Given numbers = 7.043, 7.403, 7.304

In ascending order = 7.043, 7.304, 7.403

(b) Given numbers = 0.587, 1.587, 0.1587

In ascending order = 0.1587, 0.587, 1.587

Question no – (5)

Solution :

(a) Given numbers = 47.63, 47.636, 46.736

In descending order = 47.636, 47.63, 46.736

(b) Given numbers 2.76, 2.076, 2.706

In descending order = 2.76, 2.706, 2.076

Decimals Self Practice 6E Solution :

Question no – (1)

Solution :

Given decimal number, 0.8

0.8

= 8/10

= 4/5   ….(Simplest form)

Question no – (2)

Solution :

Given decimal number, 0.25

0.25

= 25/100

= 1/4   ….(Simplest form)

Question no – (3)

Solution :

Given decimal number,  0.75

0.75

= 75/100

= 3/4    ….(Simplest form)

Question no – (4)

Solution :

Given decimal number, 0.0625

0.0625

= 625/10000

= 25/400

= 1/16   ….(Simplest form)

Question no – (5)

Solution :

Given decimal number, 0.175

0.175

= 175/1000

= 7/40    ….(Simplest form)

Question no – (6)

Solution :

Given decimal number, 9.64

9.64

= 964/100

= 241/25

= 9 16/25    ….(Simplest form)

Question no – (7)

Solution :

Given decimal number, 10.375

10.375

= 10375/1000

= 415/40

= 83/8

= 10 3/8    ….(Simplest form)

Question no – (8)

Solution :

Given decimal number, 12.408

12.408

= 12408/1000

= 1551/125    ….(Simplest form)

Question no – (9)

Solution :

Given decimal number, 20.018

20.018

= 12 51/125

= 20018/1000

= 10009/500

= 20 9/500    ….(Simplest form)

Question no – (10)

Solution :

Given decimal number, 16.325

16.325

= 16325/1000

= 653/40

= 16 13/40    ….(Simplest form)

Decimals Self Practice 6F Solution :

Question no – (1)

Solution :

(a) 9/10

= 0.9

(b) 23/10

= 2.3

(c) 6/100

= 0.06

(d) 69/100

= 0.69

(e) 657/100

= 6.57

(f) 3/1000

= 0.003

(g) 17/10000

= 0.0017

(h) 173/1000

= 0.173

(i) 6059/10000

= 0.6059

(j) 28 769/10000

= 280769/10000

= 28.0769

Question no – (2)

Solution :

(a) Given fraction, 1/4

= 0.25

(b) Given fraction, 3/5

= 0.6

(c) Given fraction, 7/8

= 0.875

(d) Given fraction, 53/116

= 3.3125

(e) Given fraction, 3/50

= 0.06

(f) Given fraction, 19 17/40

= 19.425

Question no – (2)

Solution :

Given, 18 seconds,

= 18/3600 hours

= 0.005

Hence, 18 seconds of an hour as a decimal is 0.005

Decimals Self Practice 6G Solution :

Question no – (1)

Solution :

Given, 5.9 + 36.87 + 9.265

(5.9 + 36.87 + 9.265)

= 52.035

The sum will be 52.035

Question no – (2)

Solution :

Given, 39.08 + 6.7 + 0.895 + 67.19

= (39.08 + 6.7 + 0.895 + 67.19)

= 113.865

The sum will be 113.865

Question no – (3)

Solution :

Given, 4.187 + 19.456 + 8.03 + 6.9

= (4.187 + 19.456 + 8.03 + 6.9)

= 38.573

The sum will be 38.573

Question no – (4)

Solution :

Given, 1.899 + 0.4084 + 39.76 + 8.9

= (1.899 + 0.4084 + 39.76 + 8.9)

= 50.9674

The sum will be 50.9674

For more better understanding purpose,

Question no – (5)

Solution :

Given, 5.607,38.72,605.5 and 0.7496

(5.607 + 38.72 + 605.5 + 0.7496)

= 650.5766

For more better understanding :

Question no – (6)

Solution :

Given, 372.0647, 41.62835, 0.964738 and 876

(372.0647 + 41.62835 + 0.964738 + 876)

= 1290.657788

For more better understanding :

Decimals Self Practice 6H Solution :

Question no – (1)

Solution :

Given, 79.68 – 28.46

= (79.68 – 28.46)

= 51.22

Question no – (2)

Solution :

Given, 17.09 – 16.96

= (17.09 – 16.96)

= 0.11

Question no – (3)

Solution :

Given, 9.869 – 8.1

= (9.869 – 8.1)

= 1.769

Question no – (4)

Solution :

Given, 7.1 – 0.7359

= (7.1 – 0.7359)

= 6.3641

Question no – (5)

Solution :

Given, 103.26 – 4.5746

= (103.26 – 4.5746)

= 98.6854

Question no – (6)

Solution :

Given, 51 – 29.7895

= (51 – 29.7895)

= 21.2105

∴ The answer will be 21.2105

Question no – (7)

Solution :

Given, 37.78 – 29.89672

= (37.78 – 29.89672)

= 1.88328

For more better understanding purpose

Decimals Self Practice 6I Solution :

Question no – (1)

Solution :

(a) 85 p

We know, 1 rupees = 100 paise

85/100

= 0.85

Thus, 85 p = 0.85 rupees

(b) 10 p

We know, 1 rupees = 100 paise

10/100

= 0.1

So, 10 p = 0.1 rupees.

(c) 739 p

We know, 1 rupees = 100 paise

739/100

= 7.39

Hence, 739 p = 7.39 Rupees.

(d) 7000 p

We know, 1 rupees = 100 paise

7000/100

= 70

Thus, 7000 p = 70 Rupees.

(e) 2908 p

We know, 1 rupees = 100 paise

2908/100

= 29.08

Thus, 2908 p = 29.08 Rupees

(f) 5 p

We know, 1 rupees = 100 paise

5/10

= 0.05

Therefore, 5 p = 0.05 Rupees

Question no – (2)

Solution :

(a) Rs 3.25

We know, 100 paise = 1 rupees

3.25 × 100

= 325 p

Thus, Rs 3.25 = 325 paise.

(b) Rs 37.56

We know, 100 paise = 1 rupee

37.56 × 100

= 3756 p

Hence, Rs 37.56 = 3756 paise.

(c) Rs 0.75

We know, 100 paise = 1 rupee

0.75 × 100

= 75 p

So, Rs 0.75 = 75 paise.

(d) Rs 0.09

We know, 100 paise = 1 rupee

0.09 × 100

= 9 p

So, Rs 0.09 = 9 paise.

(e) Rs 85

We know, 100 paise = 1 rupee

85 × 100

= 8500 p

Hence, Rs 85 = 8500 paise.

(f) Rs 170

We know, 100 paise = 1 rupee

176 × 100

= 17600 p

Therefore, Rs 170 = 17600 paise.

Question no – (3)

Solution :

(a) Five hundred seven rupees

In numerals = 507.00

(b) Ninety-two rupees and sixty paise

In numerals = 92.60

(c) One thousand two hundred ninety-four rupees ten paise

In numerals = 1244.10

Question no – (4)

Solution :

(a) ₹ 9.75 + ₹ 35.69

9.75 + 35.69

= 45.44 Rs.

(b) Rs 72.35 – Rs 9.63

72.35 – 9.63

= 62.67 Rs.

(c) Rs 5.36 + 87 P

5.36 + 87

= 92.36

(d) Rs 18 – 74 p

18 – 74 p

= 6.23

(e) Rs 100 – Rs 8.97

100 – 8.97

= 7.26

(f) 85 p – 25 p

85 p – 25 p

= 60 p

Decimals Self Practice 6J Solution :

Question no – (1)

Solution :

(a) 7 mm as cm

= 7/10

= 0.7 cm

So, 7 mm = 0.7 cm

(b) 59 mm as cm

We know, 10 mm = 1 cm

59/10

= 5.9

So, 59 mm = 5.9 cm

(c) 19 mm as m

We know, 1000 mm = 1 m

19/1000

= 0.019 m

Thus, 19 mm = 0.019 m

(d) 58 cm as m

We know, 100 cm = 1 m

58/100

= 0.58 m

Hence, 58 cm = 0.58 m

(e) 264 cm as m

We know, 100 cm = 1 m

∴ 264/100

= 2.64 m

So, 264 cm = 2.64 m

(f) 593 mm as m

We know, 1000 mm = 1 m

593/1000

= 0.59 m

So, 593 mm = 0.59 m

(g) 2 m as km

We know, 1000 m = 1 km

2/1000

= 0.002 km

So, 2 m = 0.002 km

(h) 75 mm as m

We know, 1000 m = 1 km

75/1000

= 0.075 km

Therefore, 75 mm = 0.075 km

(i) 930 m as km

We know, 1000 m = 1 km

930/1000

= 0.930 km

Hence, 930 m = 0.930 km

(j) 2354 m as km

We know, 1000 m = 1 km

2354/1000

= 2.354 km

So, 2354 m = 2.354 km.

(k) 935 cm as km

We know, 100000 cm = 1 km

∴ 935/100000

= 0.00935 km

Therefore, 935 cm = 0.00935 km

Question no – (2)

Solution :

(a) 8 m 23 cm as m

(8 + 0.23)

= 8.23 m

(b) Given, 83 m 4 cm as m

(83 + 0.4)

= 83.04 m

(c) 200 km 9 m as km

∴ (200 + 0.009)

= 200.009 km

(d) 7735 km 49 m as km

= 735 + 0.49 km

= 735.049 km

Question no – (3)

Solution :

(a) 8 mg as g

We know, 1000 mg = 1 gm

8/1000

= 0.008 g

So, 8 mg = 0.008 g

(b) 25 mg as g

We know, 1000 mg = 1 gm

25/1000

= 0.025 g

So, 25 mg = 0.025 g

(c) 719 mg as g

We know, 1000 mg = 1 gm

719/1000

= 0.719 g

So, 719 mg = 0.719 g

(d) 45 g 7 mg as g

We know, 1000 mg = 1 gm

45 + 0.007

= 45.007 g

So, 45 g 7 mg = 45.007 g

(e) 29.17 g as mg

We know, 1 gm = 1000 mg

29.17 × 1000

= 29170 mg

So, 29.17 = 29170 mg.

(f) 0.027 g as mg

We know, 1 gm = 1000 mg

∴ 0.027/1000

= 27 mg

Therefore, 0.027 g = 27 mg g

Question no – (4)

Solution :

(a) 598 g as kg

We know, 1000 gram = 1 kg

598/1000

= 0.598 kg

So, 598 g = 0.598 kg

(b) 69 g as kg

We know, 1000 gram = 1 kg

69/1000

= 0.069 kg

So, 69 g = 0.069 kg.

(c) 2865 g as kg

We know, 1000 gram = 1 kg

∴ 2865/1000

= 2.865 kg

So, 2865 g = 2.865 kg

(d) 7002 g as kg

We know, 1000 gram = 1 kg

7002/1000

= 7.002 kg

So, 7002 g = 7.002 kg

(e) 80 kg 5 g as kg

We know, 1000 gram = 1 kg

80 + 0.005

= 80.005 kg

So, 80 kg 5 g = 80.005 kg

(f) 12 kg 19 g as kg

We know, 1000 gram = 1 kg

12 + 0.019

= 12.019 kg

So, 12 kg 19 g = 12.019 kg

Question no – (5)

Solution :

(a) 3 mL as L

We know, 1000 ml = 1 liter

3/1000

= 0.003 L

So, 3 mL = 0.003 L

(b) 895 mL as L

We know, 1000 mL= 1 L

895/1000

= 0.895 L

So, 895 mL = 0.895 L

(c) 72 mL as L

We know, 1000 mL= 1 L

72 /1000

= 0.072 L

So, 72 mL = 0.072 L

(d) 85 L as kL

We know, 1000 L= 1 kL

85 /1000

= 0.085 kL

So, 85 L is = 0.085 kL

(e) 27 kL 105 mL as kL

We know, 1000 L = 1 kL

27 kL + 105 mL

= 27.000 105 kL

So, 27 kL 105 mL is = 27.000 105 kL

(f) 1.003 kL as L

We know, 1 kL = 1000 L

Therefore, 1.003 kL is = 1003 L

Decimals Self Practice 6K Solution :

Question no – (1)

Solution :

Man walks = 578 m, 165 m, 98 m., 631 m

Total length,

= (578 + 890 + 165 + 98 + 631)

= 2362 m

= 2.362 km

Therefore, he has walked 2.362 km.

Question no – (2)

Solution :

= 19850 m

= 6 km 760 m

= 6760 m

= 6 km 68

= 6068 m

= 19850 – (6760 + 6068)

= 19850 – 12828

= 7022

= 7 km 22 m

Hence, 7 km 22 m of road is uphill.

Question no – (3)

Solution :

Given, External diameter = 1.62 cm

= 1.62/2

= 0.81 cm

Thickness,

= 7 mm

= 0.7 cm

= 0.81 – 0.7

= 0.11 cm

Internal diameter,

= 0.11 × 2

= 0.22 cm

Therefore, the internal diameter is 0.22 cm.

Question no – (4)

Solution :

As per the question,

He withdrew = ₹ 209.98

Left money,

= (965.27 – 209.98)

= 755.29 Rs.

Thus, 55.29 Rs is left in bank.

Question no – (5)

Solution :

Total water is jug contain

= 1.5 L

= 1500 m L

Leaked out = 865 m L

= 1500 – 865

= 6.35 m L

= 1000 m L

Now, water is the jug,

= 1000 + 635

= 1635 m L

= 1.635 L

Therefore, in the jug there will be 1.635 liter water now.

Question no – (6)

Solution :

End of the 2nd week out of Sachin’s,

= (52.8 – 2.9 + 0.72) kg

= 50.62 kg

Hence, his total weight at the end of the second week is 50.62 kg.

Question no – (7)

Solution :

According to the given question,

A book is = 5 cm thick

cover is = 1.5 mm thick

Without cover thickness of book,

= [50 – (2 × 1.50] mm

= 50 – 3 mm

= 47 mm

= 4.7 cm

Therefore, the book will be 4.7 cm thick without its covers.

Next Chapter Solution :

Updated: June 17, 2023 — 11:22 am