5 Answers: A, B, D, E, F
390, 156, 78, 312, 234
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Explanation:
Since 13, 2 and 3 are required to be prime factors, this means 13*2*3 = 26*3 = 78 must be a factor of whatever we're after.
This means that we can divide each answer choice over 78 to see which results in a whole number or not
- A) 390/78 = 5
- B) 156/78 = 2
- C) 897/78 = 11.5
- D) 78/78 = 1
- E) 312/78 = 4
- F) 234/78 = 3
- G) 598/78 = 7.667 approximately
- H) 138/78 = 1.769 approximately
We can see that choices A, B, D, E and F result in whole numbers. Everything else is a decimal. So that's why 390, 156, 78, 312, and 234 are multiples of 78 and they are numbers that fit the requirements.
