Question

A bag contains $15$ red, $8$ blue and several green marbles. A marble is selected at random. The probability of drawing a blue marble is $\frac{1}{5}$.

$5$ green marbles are now taken out from the bag. If a marble is now drawn at random, find the probability of drawing a green marble

• A. $\frac{3}{10}$
• B. $\frac{12}{35}$
• C. $\frac{23}{40}$
• D. $\frac{17}{35}$

Answer 1

The correct option is B $\frac{12}{35}$

A bag contains 15 red, 8 blue and several green marbles. A marble is selected at random. The probability of drawing a blue marble is $\frac{1}{5}$.

5 green marbles are now taken out from the bag. If a marble is now drawn at random,

The green marble are $\frac{8}{P\left(E\right)}-(15+8)=40-23=17$

if 5 marbles are removed green marbles are $=17-5=12$ and total marbles 40-5=35

the probability of drawing a green marble

Probability is $P\left(E\right)=\frac{12}{35}$