The following distribution shows the daily pocket allowance of children of a locality. The mean pocket allowance is 18. Find the missing frequency k.

Daily Pocket allowance  (in rupees)

11 − 13

13 − 15

15 - 17

17 − 19

19 − 21

21 − 23

23 − 25

Number of Students

3

6

9

13

k

5

4

OR

The following frequency distribution shows the distance (in metres) thrown by 68 students in a Javelin throw competition.

Distance

0 − 10

10 − 20

20 − 30

30 − 40

40 − 50

50 − 60

60 − 70

Number of Students

4

5

13

20

14

8

4

Draw a less than type Ogive for the given data and find the median distance thrown using this curve.

This is a question of CBSE Sample Paper - Class 10 - 2017/18.

You can download the question paper here  https://www.teachoo.com/cbse/sample-papers/

The following distribution shows daily pocket allowance | distance

Question 30 - CBSE Class 10 Sample Paper for 2018 Boards - Part 2
Question 30 - CBSE Class 10 Sample Paper for 2018 Boards - Part 3 Question 30 - CBSE Class 10 Sample Paper for 2018 Boards - Part 4 Question 30 - CBSE Class 10 Sample Paper for 2018 Boards - Part 5 Question 30 - CBSE Class 10 Sample Paper for 2018 Boards - Part 6

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Transcript

Question 30 The following distribution shows the daily pocket allowance of children of a locality. The mean pocket allowance is 18. Find the missing frequency k. Daily Pocket allowance (in rupees) 11 − 13 13 − 15 15 - 17 17 − 19 19 − 21 21 − 23 23 − 25 Number of Students 3 6 9 13 k 5 4 Daily pocket allowance (in Rs) Number of workers 11 – 13 3 13 – 15 6 15 – 17 9 17 – 19 13 19 – 21 k 21 – 23 5 23 – 25 4 Class mark (xi) 12 14 16 18 20 22 24 Fixi 36 84 144 234 20k 110 96 704+20k 18(40 + k) = 704 + 20k 18(40)+ 18(k) = 704 + 20k 720 + 18k = 704 + 20k 720 – 704 = 20k – 18k 16 = 2k k = 16/2 k = 8 Distance 0 − 10 10 − 20 20 − 30 30 − 40 40 − 50 50 − 60 60 − 70 Number of Students 4 5 13 20 14 8 4 Distance (in m) Number of workers( fi ) Cumulative frequency 0 – 10 4 4 10 – 20 5 4 + 5 = 9 20 – 30 13 9 + 13 = 22 30 – 40 20 22 + 20 = 42 40 – 50 14 42 + 14 = 56 50 – 60 8 56 + 8 = 64 60 – 70 4 64 = 4 = 68 ∑▒𝑓𝑖 = 68 Distance (in m) Number of workers( fi ) Less than 10 4 Less than 20 9 Less than 30 22 Less than 40 42 Less than 50 56 Less than 60 64 Less than 70 68 ∑▒𝑓𝑖 = 68 So, N = 68 ∴ 𝑁/2 = 68/2 = 34 We draw a line parallel to x-axis where Number of students = 34 Where the line intersects the curve at x-axis, it is the median ∴ Median distance = 36 m

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.