maths
posted by joyce Rowley .
there are six red balls and nine blue balls in a box.a ball is selected at random.find the probability that the ball is (a)red(b) blue ( c) red of blue

6 red
9 blue
total is 15
prob(red) = 6/15 = 2/5
prob(blue) = 9/15 = 3/5
I assume that is a typo and should say "red or blue"
prob(red or blue) = 1
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