Aball was drawn from a bag containing 10 red, 30 white, 20 blue, and 15 yellow balls. what is the probability that it is neither red nor blue

There are a total of 75 balls in the bag.

45 of these balls are neither red nor blue.

45/75 = .60

There is a 60% chance that a ball that in not red or blue will be chosen.

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