need help with prime numbers?

Question

question
find all the pairs of prime numbers that add to 36

thankz

Answer 1

5+31

17+19

23+13

7+29

Answer 2

Better yet - I'll give you an algorithm that you can use on a calculator:

1) Make a list of prime numbers.

2) Subtract the first prime from 36.

3) If the result is also prime, then you have a valid combination.

4) Repeat until you have done all the primes including and up to 17. The primes 19...31 will of course have worked as well since the other half of your primes list will 'fall out' in the end.



If you make a short program that does this in BASIC, you can just reuse that method for as many numbers as you want. Yes, it's a homework solver tool, haha. If you understand enough to write it, then it doesn't really matter. Just don't be "rusty" when taking a quiz!

Answer 3

31 +5

29 +7

23+13

19+17