Question 6 (c)

Express the following as the sum of two odd primes:
24

Here take a look at 24, it is an even number

Now we can get an even number by adding two even numbers, but we only have 2 as an even prime number, so this case fails.

Now if we add two odd numbers we can get an even number

So possible cases are:

7 + 17 = 24
5 + 19 = 24