Question

In a game of $100$ points, $A$ can give $B$, $20$ points and $C$, $28$ points. Then, $B$ can give $C$, how many points?

Answer 1

Find the points $B$ can give to $C$:

Given that in a game of $100$ points, $A$ can give $20$ points to $B$.

$A$ can score $100$ points.

Thus, $B$ can score $(100–20)=80$ points.
And, $A$ can give $28$ points to $C$.

Thus, $C$ can score $(100–28)=72$ points.

On applying unitary method,
When $B$ scores $80$ points, $C$ scores $72$ points.
When $B$ scores $100$ points, $C$ scores $\frac{72}{80}\times 100=90$ points.
So, $B$ can give to $C$ $(100–90)=10$ points.

Hence, $B$ can give $10$ points to $C$.