There is 12/15 of a pizza left how many 3/10 pieces can be made from left over pizza?

Amount of pizza that is left = 12/15
                                            = 4/5
The size of each pizza that can be made from the left over pizza = 3/10
Then
Number of pizza's that can be made
from the left over pizza = (4/5)/(3/10)
                                      = (4 * 10)/(5 * 3)
                                     = 40/15
                                     = 8/3
                                     = 2 2/3
So 2 2/3 pizza's can be made from the pizza that is left over. I hope the above deduction is simple enough for you to understand. You can definitely use this method in future for solving similar problems without requiring any additional help from outside.