Question

the class had a pizza party 3/8 of a pizza was left over and 4/8 of a pizza with other pizza was left over you put them both into a box how much pizza do you have all together

Answer 1

That was not worded very well but I get it...

If there are 3/8 of one pizza and 4/8 of another when you put them together you add
 
3    4      7
_ + _ =   _
8    8      8

Because 3+4 = 7 and you place that over your denominator

Answer 2

You would have 7/8 of pizza slices total.