Question

Use graph paper to Solution this question.

During a medical checkup of 60 students in a school, weights were recorded as follows:

Weight (in kg)	Number of Students (f)
28 – 30	2
30 – 32	4
32 – 34	10
34 – 36	13
36 – 38	15
38 – 40	9
40 – 42	5
42 – 44	2

Taking 2 cm = 2 kg along one axis and 2 cm = 10 students along the other axis draw an ogive. Use your graph to find the:

1. median
2. upper Quartile
3. number of students whose weights is above 37 kg

Answer 1

Weight (in kg)	Number of Students (f)	Cumulative frequency (cf)
28 – 30	2	2
30 – 32	4	6
32 – 34	10	16
34 – 36	13	29
36 – 38	15	44
38 – 40	9	53
40 – 42	5	58
42 – 44	2	60

a. Here N = 60

∴ Median = `N/2`

= `60/2`

= 30^th term

= 36.2 kg  ...(From the graph)

b. Upper quartile

= `(3N)/4`

= `(3 xx 60)/4`

= 45^th term

= 38.4 kg  ...(From the graph)

c. Number of students whose weight in above 37 kg.

= 60 – 36

= 24 students.