Question 5
If m is the mid-point and l is the upper class limit of a class in a continuous frequency distribution, then the lower class limit of the class is:

A) 2m + I
B) 2m - l
C) M - l
D) M - 2I

The answer is B.
Let x and y be the lower and upper class limit of a continuous frequency distribution.
Now, mid - point of a class $=\frac{x+y}{2}=m$ [given]
$\Rightarrow x+y=2m\Rightarrow x+l=2m$
$[\because y=l=upperclasslimit(given\left)\right]$
$\Rightarrow x=2m-l$
Hence,the lower class limit of the class is 2m – l.