Ramesh had $20$ pencils, Sheelu had $50$ pencils and Jamaal had $80$ pencils. After $4$ months, Ramesh used up $10$ pencils, Sheelu used up $25$ pencils and Jamaal used up $40$ pencils. What fraction did each use up? Check if each has used up an equal fraction of her/his pencils?

Given

The total number of pencils Ramesh had $=20$.

The total number of pencils Sheelu had $=50$.

The total number of pencils Jamaal had $=80$.

The number of pencils used by Ramesh $=10$.

$\Rightarrow$Fraction of pencils used $=$ $\frac{\mathrm{Number}\mathrm{of}\mathrm{pencils}\mathrm{used}}{\mathrm{Total}\mathrm{number}\mathrm{of}\mathrm{pencils}}=\frac{10}{20}=\frac{1}{2}$

The number of pencils used by Sheelu $=25$.

$\Rightarrow$Fraction of pencils used $=\frac{\mathrm{Number}\mathrm{of}\mathrm{pencils}\mathrm{used}}{\mathrm{Total}\mathrm{number}\mathrm{of}\mathrm{pencils}}=\frac{25}{50}=\frac{1}{2}$

Number of pencils used by Jamaal $=40$.

$\Rightarrow$Fraction of pencils used $=\frac{\mathrm{Number}\mathrm{of}\mathrm{pencils}\mathrm{used}}{\mathrm{Total}\mathrm{number}\mathrm{of}\mathrm{pencils}}=\frac{40}{80}=\frac{1}{2}$

Hence, each has used up an equal fraction of pencils which is $\frac{1}{2}$.