Let x = ounces of $35 perfume
Let y = ounces of $15 perfume.
We want a 3-ounce perfume, therefore
x + y = 3
or
y = 3 - x (1)
We want the 3-ounce perfume to cost $63. Therefore
35x + 15y = 63 (2)
Substitute (1) in (2).
35x + 15(3 - x) = 63
35x + 45 - 15x = 63
20x = 63 - 45 = 18
x = 18/20 = 0.9
From (1), obtain
y = 3 - 0.9 = 2.1
Answer:
0.9 ounces of $35 perfume and 2.1 ounces of $15 perfume.
