Nicole has a machine that will produce a number from 1 through 50 when she pushes a button. if she pushes the button, what is p(multiple of 10), p(not 100), p(not a multiple of 4), p(one-digit number)?

Number from 1 through 50. 50 possible numbers.
multiple of 10 : 10, 20, 30, 40, 50. 5 possible events.
multiple of 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48. 12 possible events
one-digit number: 1, 2, 3, 4, 5, 6, 7, 8, 9. 9 possible events

P(multiple of 10) = 5/50 or 1/10
P(not 100) = 50/50 or 1
P(not a multiple of 4) =  38/50 or 19/25 
P(one-digit number) = 9/50

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