Find missing frequency for interval 40-49

Question

Interval	Frequency	Relative frequency
22-29	4	0.16
30-39	6	0.24
40-49	?	0.40
50-59	5	0.20
Total		1.00

Answer 1

There are N statistics

4 of them are between 22 and 29, which is also 16% =0.16 of them

4 = 0.16 N

400 = 16 N

400/16 = N

200/8 =N

100/4 = N

25 = N

So there are 25 statistics.

40% = 0.4 of 25 is 10, so there are 10 stats between 40 and 49