Question

A bag contains $672$ red balls and $n$ green balls. If the probability of drawing green balls is three times that of red ball., find the total number of balls.

• A. $2016$
• B. $2015$
• C. $2020$
• D. $2688$

Answer 1

The correct option is A $2016$

Total no: of balls $=672+n$

(red) (green)

$P$(red balls) $=\frac{672}{672+n}$

$P$ (green balls ) $=\frac{n}{672+n}$

Acc to Ques=

$3\left(\frac{672}{672+n}\right)=\left(\frac{n}{672+n}\right)$

$3\times 672=n$

$\therefore n=2016$

Option $A$ is correct