R d sharma solutions mathematics class 9 Solutions for Chapter 22 tabular representation of statistical data

What do you understand by the word “statistics” in:

(i) singular form

(ii) plural form?

What are

(i) primary data

(ii) secondary data?

Which of the two—the primary or the

secondary data—is more reliable and why?

Why do we group data?

The monthly pocket money of six friends is given below:

Rs 45, Rs 30, Rs 40, Rs 50, Rs 25, Rs 45.

(i) What is the highest pocket money?

(ii) What is the lowest pocket money?

(iii) What is the range?

(iv) Arrange the amounts of pocket money in ascending order

The final marks in mathematics of 30 students are as follows: 53, 61, 48, 60, 78, 68, 55, 100, 67, 90, 75, 88, 77, 37, 84, 58, 60, 48, 62, 56, 44, 58, 52, 64, 98, 59, 70, 39, 50, 60. (i) Arrange these marks in ascending order, 30 to 39 one group,40 to 49 second group etc. Now answer the following: (ii) What is the highest score? (iii) What is the lowest score? (iv) What is the range? (v) If 40 is the pass mark how many have failed? (vi) How many have scored 75 or more? (vii) Which observations between 50 and 60 have not actually appeared? (viii) How many have scored less than 50?

The weights of new born babies (in kg.) in a hospital on a particular day are as follows:

2.3, 2.2, 2.1, 2.7, 2.6, 3.0, 2.5, 2.9, 2.8, 3.1, 2.5, 2.8, 2.7, 2.9, 2.4

(i) Rearrange the highest weight.

(ii) Determine the highest weight.

(iii) Determine the lowest weight.

(iv) Determine the range.

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

(vi) How many babies weigh below 2.5 kg?

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

(viii) How many babies weigh 2.8 kg?

The number of runs scored by a cricket player in 25 innings is as follows:

26, 35, 94, 48, 82, 105, 53, 0, 39, 42, 71, 0, 64, 15, 34, 15, 34, 6, 71, 0, 64, 15, 34, 15, 34, 67, 0, 42, 124,

84, 54, 48, 139, 64, 47

(i) Rearrange these runs in ascending order.

(ii) Determine the player, is highest score.

(iii) How many times did the player not score a run?

(iv) How many centuries did he score?

(v) How many times did he score more than 50 runs?