Question 232881: A spinner has 1 through 21.What is the probability that the spinner will stop on an even number or a multiple of 3?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A spinner has 1 through 21.What is the probability that the spinner will stop on an even number or a multiple of 3?
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Evens: 2,4,6,8...16,18,20
How many?: 10
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3 multiples: 3,6,9,12,15,18,21
How many?: 7
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Numbers that are both:
6,12,19
How many?: 3
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P(even or 3-mult) = P(even) + P(3-mult) - P(even AND 3-mult)
P(even or 3-mult) = 10/21 + 7/21 - 3/21 = 14/21 = 2/3
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Cheers,
Stan H.
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