Just dividing the volumes of the pan, 189 and one bar, 3, suggests that at most she'll be able to cut 63 bars.
But you'll also have to prove that you can divide it in a regular pattern. And you can:
9 divides by 1
10.5 divides by 1.5
2 divides by 2.
So no incomplete bars!
F(x)·g(x) = (3x +4)·(5 -x) = -3x^2 +11x +20
(f·g)(x) = -3x^2 +11x +20
At the first store, Julia spent 50 dollars. Since 20 percent is 100 divided by 5, you multiply the 10 dollars by 5 to get 50 dollars.
At the second store, Julia spent. Since 12 dollars is 20 percent, multiply 12 dollars by 5 to get 60 dollars.
50+60= 110. Julia spent 110 dollars altogether.<span />