You can put this solution on YOUR website! The easiest way to do this is to find a common denominator.
Since 5 goes into 15, we'll use that.
3/5 = how many 15ths?
Multiply by 3 across
3*3 = 9; 5*3 = 15
9/15
Now add the 4/15ths
9 pieces of pizza in a 15 piece pie + 4 pieces of pizza in a 15 piece pie =
13 pieces of pizza in a 15 piece pie
13/15