Question

PLEASE HELP!! Explain your answer!
Alex sold 330 candy bars to raise money for his community basketball league. Milk chocolate candy bars sold for $2 each, and white chocolate candy bars sold for $3 each. Alex sold $900 worth of candy bars.

How many white chocolate candy bars did Alex sell?

Answer 1

eg. x is the number of milk chocolate candy bars, y is the number of white chocolate of candy bar

x + y = 330
2x + 3y = 900

From first equation
x + y = 330
x = 330 - y

From second equation, subtitute x with 330 - y
2x + 3y = 900
2(330-y) + 3y = 900
660 - 2y + 3y = 900
660 + y = 900
y = 900-660
y = 240

The number of white chocolate candy bars is 240