There are 57 ounces of cereal in 5 boxes. At this rate, how many ounces of cereal are in 8 boxes?

91.2 ounces

Step-by-step explanation:

Let's make a proportion using this setup:

ounces/boxes=ounces/boxes

There are 57 ounces in 5 boxes, and x ounces in 8 boxes.

57 ounces/5 boxes= x ounces/8 boxes

57/5=x/8

Now we have to solve for x. x and 8 are being divided. To undo this, multiply both sides by 8, because multiplication is the opposite of division.

8*57/5=x/8*8

The 8s on the right will cancel, so we are left with:

8*57/5=x

8*11.4=x

91.2=x

There are 91.2 ounces in 8 boxes