Suppose that is the product of three consecutive integers and that is divisible by . Which of the following is not necessarily a divisor of ?
Pick one
Solution
Solution 1
Whenever is the product of three consecutive integers, is divisible by , meaning it is divisible by .
It also mentions that it is divisible by , so the number is definitely divisible by all the factors of .
In our answer choices, the one that is not a factor of is .
Solution 2
We can look for counterexamples. For example, letting , we see that is not divisible by 28, so is our answer.
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