There are 18 composite numbers up to and including 30
30
To find two numbers that add up to 18, we can set up an algebraic equation. Let's call the two numbers x and y. The equation we need to solve is x + y = 18. Since we are looking for two numbers that add up to 18, there are multiple possible solutions. For example, one possible pair of numbers that add up to 18 is 10 and 8, as 10 + 8 = 18.
35
It is impossible for three prime numbers less than 30 to add up to 1955. After all, 30+30+30 is only 90.
There are 5 numbers in your list. Add them up and divide by 5.
15
None add up to 30; you would need at least three 6-sided die with numbers 6-11 to add to 30.
33
2+5+11= 18.
They are 29, 30 and 31.
552