Question 1192038
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Answers:
a) 2/25
b) 9/25
c) 16/25
d) 12/25


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Explanation on how I got those answers:


Part (a)


There are 2 chips we want out of 25 total.
Therefore, 2/25 is the probability of getting either a "7" or a "15".


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Part (b)


Event space = {3, 5, 6, 9, 12, 15, 18, 21, 24}
The event space is the set of stuff we want to happen, which is getting a multiple of 3 or getting "5".
There are 9 numbers in that list.


This is out of 25 total items in the sample space. 


That's why 9/25 is the answer.


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Part (c)


A = number is even = {2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24}
B = number is divisible by 3 = {3, 6, 9, 12, 15, 18, 21, 24} 
Each item in either set above must be between 1 and 25.


C = the number is even, or divisible by 3, or both 
C = A union B
C = {2, 3, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24}


All of the items in set C represent stuff we want to happen. 
There are 16 values in set C out of 25 values total.


Answer: 16/25


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Part (d)


A = number is divisible by 3 = {3, 6, 9, 12, 15, 18, 21, 24} 
B = number is divisible by 4 = {4, 8, 12, 16, 20, 24}


C = the number is divisible by 3, or divisible by 4, or both
C = A union B
C = {3, 4, 6, 8, 9, 12, 15, 16, 18, 20, 21, 24}


There are 12 items in set C out of 25 total.


The probability of getting a number divisible by 3, divisible by 4, or both is 12/25

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