Consuela and her three friends order 2 pizzas. consuela cuts each pizza into 8 equal slices. she saves 2 slices of pizza for her older brother, then she and her friends share the rest of the pizza, each eating the same number of slices. what fraction of the 2 pizzas is left over?

Let
x>  the number of slices eating by Consuela  and her three friends

we know that
[total slices]=8*2=16 slices
[slices of pizza for her older brother]=2
x=16-2=14 slides
Consuela and her friends share the rest of the pizza, each eating the same number of slices> 14/4= 3.5 slides of pizza each  (this part is not necessary, but it is shown in a didactic way)

the question is 
What fraction of the 2 pizzas is left over?
[slices of pizza for her older brother]/[total slices]=2/16=1/8

the answer is (1/8)