Question

Suppose the number $1155$ is written as the product of three positive integers. What is the smallest possible value of the sum of those three integers?

Answer 1

First off, let us find for the prime factors of this number, 1155. The prime factors are:

3 * 5 * 7 * 11 = 1155

3, 5, 7, 11

Since there are 4 prime factors, we multiply the two smallest prime factors to make this into three, so multiply 3 and 5, so:

15, 7, 11

Now the smallest possible sum is:

15 + 7 + 11 = 33

Answer:

33