Question

The fifth graders are planning a pizza party. Each fifth grader will eat two slices of pizza with a favorite topping. One-half of the students want pepperoni. One-fourth of the students want xtra cheese. One-eighth of the students want sausage. Four students want mushrooms. How many students select a favorite topping for their pizza slices?

Answer 1

32 students choose a favorite topping for their slices.

Let x be the total number of students.

1/2 of the total students, or 1/2x, choose pepperoni.
1/4 of the total students, or 1/4x, choose extra cheese.
1/8 of the total students, or 1/8x, choose sausage.
4 students choose mushrooms.

We know that together, these equal the total number of students, x:
1/2x+1/4x+1/8x+4=x

We will use 8 as the common denominator:
4/8x+2/8x+1/8x+4=x


Combining like terms:
7/8x+4=x

Subtract 7/8x from both sides:
7/8x+4-7/8x=x-7/8x
4=1x-7/8x
4=1/8x

Divide both sides by 1/8:
4÷(1/8) = 1/8x÷(1/8)
4/1÷(1/8) = x
4/1×8/1 = x
32/1 = x
32 = x