SOLUTION: A spinner has regions numbered 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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Question 1089244: A spinner has regions numbered 1 through 21. What is the probability that the spinner will stop on an even number or a multiple of 3?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
Among the numbers from 1 to 21,
there are 10 even numbers, from 1%2A2=2 to 10%2A2=20 ;
there are 7 multiples of 3, from 1%2A3=3 to 7%2A3=21 ,
including 3 multiples of 6 (even and multiples of 3), from 1%2A6=6 to 3%2A6=18 .
Those multiples of 6 would be counted doubly, so among the numbers from 1 to 21,
there are 10%2B7-3=14 that are either even and/or multiple of 3.
The probability that the spinner will stop on one of those 14 numbers is
14%2F21=highlight%282%2F3%29 .