**Rd Sharma Solutions Class 6 Chapter 21 Data Handling – I Presentation of Data**

Welcome to NCTB Solution. Here with this post we are going to help 6th class students for the Solutions of Rd Sharma Class 6 Mathematics, Chapter 21, Data Handling – I (Presentation of Data) . Here students can easily find Exercise wise solution for chapter 21, Data Handling – I (Presentation of Data) . Students will find proper solutions for Exercise 21.1. Our teachers solved every problem with easily understandable methods so that every students can understand easily. Here all solutions are based on the CBSE latest curriculum.

**Data Handling – I (Presentation of Data) Exercise 21.1 Solution**

**Question – (1) **

**Solution : **

**(i)** The active acquisition of information which is obtained from a primary source is called observation.

**(ii)** Data is a collection of facts such as value measurements.

**(iii)** The number of times of an observation occurs in the given data, is called frequency of the observation.

**(iv)** Frequency distribution is a method to present raw data in the from which one can easily understand the information contained in the raw data.

**Question – (2) **

**Solution : **

**(i)** Arrange these marks in the ascending order. 30 to 39 one group, 40 to 49 second group etc.

**Frequency desaturation table :**

30 – 39 = 37, 39 |

40 – 49 = 44, 48, 48 |

50 – 59 = 50, 52, 53, 55, 55, 58, 58, 59 |

60 – 69 = 60, 60, 60, 61, 62, 64, 67, 68, |

70 – 79 = 70, 75, 77, 78 |

80 – 89 = 84, 88 |

90 – 99 = 90, 98 |

100 – 109 = 100 |

**(ii)** What is the highest score?

= The highest score is 100

**(iii)** What is the lowest score?

= The lowest score is 37

**(iv)** What is the range?

= Range is

= (100 – 37)

= 63

**(v)** If 40 is the pass mark how many have failed?

= 2 Students have failed.

**(vi)** How many have scored75 or more?

= 8 Students have scored 75 or more

**(vii)** Which observations between 50 and 60 have not actually appeared?

= 51, 54, 57 observations.

**(viii)** How many have scored less than 50?

= 5 students have scored less than 50

**Question – (3) **

**Solution : **

**(i)** Rearrange the weights in descending order.

In descending order,

3. 1, 3.0, 2.9, 2, 8, 2.8, 2.7, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1

**(ii)** Determine the highest weight

= The highest weight

= 3.1 kg

**(iii)** Determine lowest weight.

= The lowest weight

= 2.1 kg

**(iv)** Determine the range

= Range = (3.1 – 2.1) kg

= 1kg

**(v)** How many babies were born on that day?

= 15 babies born on that day.

**(vi)** How many babies weigh below 2.5 kg?

= 4 babies weight below 2.5 kg

**(vii)** How many babies weigh more than 2.8 kg?

= 4 babies weight more than 2.8 kg

**(viii)** How many babies weigh 2.8 kg?

= 2 babies weight 2.8 kg

**Question – (4) **

**Solution : **

No of children |
Tally marks |
Frequency |

0 | IIII | 5 |

1 | IIII II | 7 |

2 | IIII IIII | 11 |

3 | IIII | 5 |

4 | IIII I | 6 |

5 | III | 3 |

6 | III | 3 |

**Question – (5) **

**Solution : **

Marks |
Tally marks |
Frequency |

7
14 16 17 19 21 22 27 29 31 33 34 37 38 39 41 42 43 44 47 49 51 52 53 54 57 59 61 62 67 |
II
I I I I I I II I I II I IIII II IIII I IIII I I I I I III I III I I II I I I |
2
1 1 1 1 1 1 2 1 1 2 1 4 2 4 1 6 1 1 1 1 3 1 3 1 1 2 1 1 1 |

**Question – (6) **

**Solution : **

Scores |
Tally marks |
No of them |

1 | IIII / | 5 |

2 | IIII / | 5 |

3 | IIII | 4 |

4 | III | 3 |

5 | IIII | 4 |

6 | IIII | 4 |

**Question – (7) **

**Solution : **

Here, Number of

Accidents |
Tally marks |
No of days |

0 | || | 2 |

1 | ||| | 3 |

2 | ||||/ | | 6 |

3 | ||| | 3 |

4 | |||| | 4 |

5 | ||||/ I | 6 |

6 | ||||/ | 6 |

**Question – (8) **

**Solution : **

Ages |
Tally marks |
No of students |

12 | IIII | 4 |

13 | IIII/ IIII/ II | 12 |

14 | IIII/ IIII | 9 |

15 | II | 2 |

16 | II | 2 |

17 | I | 1 |

**Question – (9) **

**Solution : **

Frequency table :

Wagon |
Tally works |
No of worker |

150 | III | 3 |

200 | IIII/ | 5 |

250 | IIII | 4 |

300 | II | 2 |

350 | I | 1 |

**(i)** What is the range in wages (in Rs)?

= Range in wages

= (350 – 150) Rs

= 200 Rs

**(ii)** How many Workers are getting Rs 350?

= Only 1 worker getting Rs 350

**(iii)** How many workers are getting the minimum wages?

= 3 workers getting minimum wage Rs 150

**Question – (10) **

**Solution : **

Marks obtained History |
Tally marks |
No of students |

9 | IIII/ I | 6 |

12 | IIII | 4 |

17 | IIII | 4 |

18 | II | 2 |

19 | IIII | 4 |

20 | III | 3 |

25 | II | 2 |

**(i)** What is the range of marks?

Range is,

= (25 – 9)

= 15

**(ii)** What is the highest mark?

= The highest mark is = 25

**(iii)** Which mark is occurring more frequently?

= Observation 9

**Question – (11) **

**Solution : **

Mark obtained :

Mathematics |
Tally mark |
No of students |

1 | II | 2 |

2 | III | 3 |

3 | III | 3 |

4 | IIII/ II | 7 |

5 | IIII/ I | 6 |

6 | IIII/ II | 7 |

7 | IIIII | 5 |

8 | IIII | 4 |

9 | III | 3 |

**(i)** Find how many students obtained marks equal to or more than 7?

= Students got marks equal to or more than 7

= 5 + 4 + 3

= 12

**(ii)** How many students obtained marks below 4?

No of students who got mark below 4

= 2 + 3 + 3

= 8

**Question – (12) **

**Solution : **

**(i)** Arrange the mane of sweets in a table using tally marks.

Sweets |
Tally marks |
Frequency |

Ladoo | IIII/ IIII/ II | 12 |

Barfi | III | 3 |

Jalebi | IIII/ I | 6 |

Rasogulla | IIII/ IIII | 9 |

**(ii)** Which sweet is preferred by most of the students.

= Ladoo, sweet is prefaced by most of the students.

**Previous Chapter Solution : **

👉 Chapter 21 👈