Math
posted by Frank on .
On a Christmas package, Audrey needs to use only 40cent stamps and 16cent stamps. If she uses twice as many 40cent stamps as 16cent stamps, how many of each type of stamp must she use to mail a package costing $5.76 in postage?

number of 16 cent stamps  x
number of 40 cent stamps  2x
16x + 40(2x) = 576
96x = 576
x = 6
.... state your consclusion