Question

The class marks of a frequency distribution are
15, 20, 25, 30,...... The class corresponding to
the class mark 25 is
O 12.5 - 17.5
20.5 - 29.5
18.5-21.5
22.5 – 27.5

Answer 1

Answer:

Given, CM= 15,20,25,30,35.....

Since the CM are of equal width, then class size= 20-15=5

Using the formula:

a+(h/2) and a-(h/2), Where a= CM and h=class size

Substituting,

20+(5/2)=20+2.5=22.5

20-(5/2)=20-2.5=17.5

Therefore, class (CM=20) is 22.5-17.5

Again,  

25+(5/2)=25+2.5=27.5

and 25-(5/2)=25-2.5=22.5

Therefore, Class= 22.5-27.5

Step-by-step explanation:

GIVEN