Question

The following bar graph (Fig.) represents the heights (in cm) of 50 students of Class XI of a particular school. Study the graph and answer the following questions:

(i) What percentage of the total number of students have their heights more than 149 cm?

(ii) How many students in the class are in the range of maximum height of the class?

(iii) The school wants to provide a particular type of tonic to each student below the height of 150 cm to improve his height. If the cost of the tonic for each student comes out to be Rs. 55, how much amount of money is required?

(iv) How many students are in the range of shortest height of the class?

(v) State whether true or False:

(a) There are 9 students in the class whose heights are in the range of 155 -159 cm.

(b) Maximum height (in cm) of a student in the class is 17.

(c) There are 29 students in the class whose heights are in the range of 145 -154 cm.

(d) Minimum height (in cm) of a student is the class is in the range of 140 -144 cm.

(e) The number of students in the class having their heights less than 150 cm is 12.

(f) There are 14 students each of whom has height more than 154 cm.

Answer 1

(i) The total number of students that have their height more than 149 cm

= 16 + 15 + 5 = 31

The % of students that have their height more than 149 cm

= \(\frac{31}{50}\) × 100

= 62%

(ii) The number of students in range of maximum height of the class = 5

(iii) Total number of students below height of 150 cm

= 7 + 12

= 19

The cost of the tonic for each student = Rs. 55

The cost of the tonic for 19 student = 55 × 19

= Rs. 1045

(iv) The number of students that are in the range of shortest height of the class = 7

(v) (a) The statement is true.

(b) The given statement is false.

(c) The total number of students in the range of 145 - 154

= 12 + 17

= 29

So, the given statement is true.

(d) The given statement is true.

(e) The given statement is false.

(f) The number of students whose height is more than 154 cm

= 9 + 5

= 14

So, the given statement is true.