Question

The probability of selecting a blue marble at random from a jar that contains only blue, black and
green marbles is 1/5. The probability of selecting a black marble at random from the same jar is
1/4. If the jar contains 11 green marbles, find the total number of marbles in the jar.​

Answer 1

Step-by-step explanation:

Given that

P(b) =1/5

P(black)=1/4

P(g)

WE know that

P(b) +p(Black) +p(g) =1

1/5+1/4 +p(g) =1

P(g)=11/20

We know that p(g) =(no of green marbles) /(total no of marbles)

So

11/x =11/20

X=20

Total no of marbles..