Here is the prime numbers under 100.
since yours are consecutive it is probably the 2 before 55 and the two after 55.
See if that works. (I have not tried it )
Yes that does work :))
Let's divide 220 by 3 we will get 73.3333
So one of the prime no's is 73 and it should be the middle one
previous one is 71
Next one is 76
Check: 71+73+76 = 220
N.T
Sorry i was wrong in the previous abswer as 76 is not prime. Melody you are genious... In all cases they cannot be three numbers because the sum of units must end up with entire tens (220) and the prime numbers end with 3, 7, 9 and 1... The numbers 3+7 =10 and 9+1=10 .. they can never be three numbers.
N.T