Question

If there are 3 blue marbles, 2 red marbles, and 1 green marble in a bag, what is the probability of drawing a blue marble if you already drew 1 blue marble and did not replace it?

Answer 1

The probability of drawing a blue marble out a bag

⇒ is the number of blue marbles over the total number of marbles in

the bag

However, since one blue marble was already drawn out

⇒ we must minus one from the total blue marbles

⇒we must also minus one from the total marble

Thus the probability is

`(Number-of-Blue-Marbles)/(Total-Number-of-Marbes) =(2)/(5)`

Answer: 2/5

Hope that helps!