Gordo ate 3 twinkles and 1 cupcake, for a total of 750 calories. A cupcake
has twice as many calories as a
twinkie. How many calories are in a
twinkie? How many calories are in a
cupcake?

To answer this, we can use as 1 Twinkie as x, and a cupcake as y. First, we can make an equation. Since 3 Twinkie’s and 1 cupcake add up to 750 calories, we have: 3x+y=750. Since a cupcake has twice the amount of calories, then 2x=y. Next, we can substitute the y, and we get:
3x+2x=750
Combining like terms
5x=750
Divide by 5 on both sides
x = 150
Since a cupcake has twice the amount of calories than a Twinkie, then one Twinkie is 150*2=300.