The number of pepperoni slices that kim puts on a pizza varies directly as the square of the diameter of the pizza. If she puts 15 slices on a 10" diameter pizza, how many slices should she put on a 16" diameter pizza?

You can make this into a fraction, and then simplify it.

15/10, right?

15/10 = 3/2

Then compare 3/2 to the rest of the equation

3/2 = x/16

2 * 8 = 16

so

3 * 8 = x

x = 24

Kim would put x number of pizza slices on her pizza.

So she would be putting on 24 slices on her pizza.

Varies directly as the square of the diameter

square means to multiply by itself or x^2

that means

k=x/y

in this case

x=15

y=10^2

k=15/10^2=15/100=3/20

so the new pizza is

k=x/16^2

k=3/20

3/20=x/16^2

evaluate 16^2

3/20=x/256

multiply both sides by 256

768/20=x

384/10=x

38.4=x

she should put about 38 slises