well, the primes less than 20 are
2,3,5,7,11,13,17,19
So, pick all the pairs that add up to less than 20.
how many positive intergres less than 20 are equal to the sum of two different prime number?
2 answers
2+3=5,2+5=7,2+7=9,2+11=13,2+13=15,2+17=19,
3+5=8, 3+7=10, 3+11=14, 3+13=16,
5+7=12, 5+11=16, 5+13=18,
7+11=18
So, is 14
am i right?
3+5=8, 3+7=10, 3+11=14, 3+13=16,
5+7=12, 5+11=16, 5+13=18,
7+11=18
So, is 14
am i right?