The sum of three distinct primes is 20. What is their largest possible product?

154

Step-by-step explanation:

Primes less than 20 are:

2, 3, 5, 7, 11, 13, 17, 19

Possible combinations that add up to 20 are:

2 + 5 + 13

2 + 7 + 11

The products are:

2 * 5 * 13 = 130

2 * 7 * 11 = 154

So the largest possible product is 154.