Question

The first of two films lasted 3 minutes less than twice as long as the second. Together the two films lasted 132 minutes. How long was the first film?

Answer 1

x = first film....y = second film

x + y = 132
x = 2y - 3

2y - 3 + y = 132
3y - 3 = 132
3y = 132 + 3
3y = 135
y = 135/3
y = 45......so the 2nd film lasted 45 minutes

x = 2y - 3
x = 2(45) - 3
x = 90 - 3
x = 87 <=== the first film lasted 87 minutes