Let m be the midpoint and u be the upper class limit of a class in a continuous frequency distribution.
Question:
Let m be the midpoint and u be the upper class limit of a class in a continuous frequency distribution. The lower class limit of the class is
(a) 2m − u
(b) 2m + u
(c) m − u
(d) m + u
Solution:
(a) 2m
Given:
Mid value = m
Upper limit = u
We know:
$\frac{\text { Lower limit+Upper limit }}{2}=$ Mid value
$\Rightarrow \frac{\text { Lower limit }+u}{2}=m$
$\Rightarrow$ Lower limit $+u=2 m$
$\Rightarrow$ Lower limit $=2 m-u$