SOLUTION: A ball is drawn at random from a box containing 7 red balls, 4 white balls and 6 yellow balls. Determine the probability that it is a) red b) yellow c) not white d) white or

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Question 947751: A ball is drawn at random from a box containing 7 red balls, 4 white balls and 6 yellow balls.
Determine the probability that it is
a) red
b) yellow
c) not white
d) white or yellow
Answer by DrBeeee(684) About Me  (Show Source):
You can put this solution on YOUR website!
The sample universe is 7 red(r), 4 white(w) and 6 yellow(y) for a total of 17 balls (possible outcomes).
Probability = (number of favorable outcomes)/(total number of possible outcomes)
a) P(r) = 7/17
b) P(y) = 6/17
c) P(not w) = P(r or y) = P(r) + P(y) - P(r and y) or
P(not w) = 7/17 + 6/17 - 0 = 13/17 or
P(not w) = 1 - P(w) = 1 - 4/17 = 13/17
d) P(w or y) = P(w) + P(y) - P(w and y) or
P(w or y) = 4/17 + 6/17 - 0 = 10/17 or
P(w or y) = P(not r) = 1 - P(r) or
P(w or y) = 1 - 7/17 = 10/17