On a Christmas package, Audrey needs to use only 40-cent stamps and 16-cent stamps. If she uses twice as many 40-cent stamps as 16-cent stamps, how many of each type of stamp must she use to mail a package costing $5.76 in postage?
How can i set this up? I need help please.
If there are x at 40 cents, and y at 16 cents, then you know that
x = 2y
40x+16y=576
To solve this problem, we can set up a system of equations. Let's assume Audrey uses x 16-cent stamps and 2x 40-cent stamps.
The value of the 16-cent stamps is 16x cents, and the value of the 40-cent stamps is 40(2x) or 80x cents.
So, the total value of the stamps used is 16x + 80x = 96x cents.
We know that the total postage cost is $5.76, which is equal to 576 cents.
Now we can set up the equation:
16x + 80x = 576
Combining like terms, we have:
96x = 576
To solve for x, divide both sides of the equation by 96:
96x/96 = 576/96
x = 6
So, Audrey needs to use 6 of the 16-cent stamps and 2(6) = 12 of the 40-cent stamps.