Algebra Question!!!?

Question

Betty's diner makes 15% profit on its lunches and 22% profit on its dinners. If the diner took $2700 on Tuesday and made $524 profit, how much was spent at lunch? Let x represent the sales at lunch and y represent the sales at dinner, write two equations, then solve.

♥Thanks♥

Answer 1

X = sales at lunch
Y = sales at dinner

X + Y = 2700
( .15 ) X + ( .22 ) Y = 524

Use the first equation to isolate X, then substitute into the second.

X = 2700 - Y

Then

( .15 ) ( 2700 - Y ) + ( .22 ) Y = 524

Solve for Y, then get X from the first equation.