A box contains 4 red pens, 5 blue pens, and 9 green pens. Two pens are drawn out of the box without replacement. What is the probability of drawing a red pen on the first draw and the same color pen on the second draw?

1 answer

The probability of a red pen on the first draw is 4/18.
For the second draw, there are 3 red pens left out of 17 pens total.
The probability of both happening is obtained by multiplying the two probabilities:
P(RR)=(4/18)*(3/17)=2/51