Question

In a frequency distribution, the mid-value of a class is 12 and the class-size is 20. The lower limit of the class is ______.

विकल्प

• 2

• 8

• 10

• 12

Answer 1

In a frequency distribution, the mid-value of a class is 12 and the class-size is 20. The lower limit of the class is 2.

Explanation:

Let lower limit = L and upper limit = U.

Class-mark (mid-value) `m = (L + U)/2 = 12` and class-size h = U – L = 20.

So, U = L + 20.

Substitute:

`(L + (L + 20))/2 = 12`

⇒ `(2L + 20)/2 = 12`

⇒ L + 10 = 12

⇒ L = 2