You are not giving enough information but in one of the calsses the average of student's height might be greater than the other class beacause one of the two classes needs to have 1 extra person than the other calss
It’s prob 20 or 30 Bc 18 is rounded to 20 and 29 is rounded to 30

x

1 x 5 = 5
16 x 4 = 64
is the answer
In simplest form the answer would be

because it cant be divided any farther.
I think the answer is 504
hope this helps can i plz get brainliest