The sum of three different numbers is 18. lf every number is a prime number, what are the three numbers?

1 Answer

#(2,3,13)# and #(2,5,11)#

Explanation:

The sum of three odd numbers is always odd. Thus, #18# cannot be the sum of three odd primes.

In other words, one of the numbers must be #2#, the only even prime.

Now, we just need to find two primes that sum up to #16#.

The only prime numbers we can use are: #3,5,7,11,13#

By trial and error, #3+13# and #5+11# both work.

Therefore, there are two possible answers: #(2,3,13)# and #(2,5,11)#.