Question

A bag contains 18 balls out of which x balls are red
1.if one ball is drawn at random from the bag, what is the probability is not red
2.if 2 more red balls are put in bag, probability cost of drawing a red ball will be 9 upon 8 times the probability of drawing red ball in the first case find the value of x

Answer 1

Possible outcomes {18}
1) favorable outcomes {18-x}
Probability 18-x/18
2) PROBABILITY OF RED BALLS = x+2
x+2/18 = 9/8
162 = 8x +2
8x=160
X=20