A display case of glitter stickers are marked 15 for $2. If Cathy wants to buy 30 glitter stickers, how much will Cathy spend?

$4, 15 x 2=30

      2 x 2=4

4 dollars

Step-by-step explanation:

We can write a ratio to solve

15 stickers       30 stickers

=

2 dollars           x stickers

Using cross products

15x = 2*30

15x = 60

Divide by 15

15x/15 = 60/15

x = 4

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