SOLUTION: a spinner is numbered 1-50. if you spin one time, what is the probability you will get: a) a multiple of 7? b) an even number between 20 and 30?

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Question 294138: a spinner is numbered 1-50. if you spin one time, what is the probability you will get: a) a multiple of 7? b) an even number between 20 and 30?
Answer by Earlsdon(6294) (Show Source):
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a)How many multiples of 7 are there between 1 and 50?
1*7 = 7
2*7 = 14
3*7 = 21
4*7 = 28
5*7 = 35
6*6 = 42
7*7 = 49
There are 7 multiples of 7 so you take 7 and divide it by 50 (the total number of numbers) to get 0.14 or 14%
So the probability is 14%.
b) How many even numbers are there between 20 and 30. You didn't say whether or not to include the numbers 20 and 30 and "between" usually means not including, so the even numbers between 20 and 30 are:
22, 24, 26, 28, or four of them so take 4 and divide it by the total number of numbers, that's 50 to get 0.08 or 8%
So the probability is 8%.
But if you were to include the numbers 20 and 30 then there would be 6 even numbers between 20 and 30 so the probability would then be or 12%