Mary ellen baked 15 cupcakes, and her children ate 2⁄3 of them. how many cupcakes did they eat?

First, divide 15 by 3 = 5
5 x 2 = 10
10 cupcakes

Another way to do this:
15/1 x 2/3 = 30/3
30/3 = 10 cupcakes

Hope this helps!

15/3 = 5, so if 1/3 = 5 then 2/3 = 10