Question

Two mechanics worked on a car. The first mechanic charged $55 per hour, and the second mechanic charged $90 per hour. The mechanics worked for a combined total of 25 hours, and together they charged a total of $1900. How long did each mechanic work?

Answer 1

55x+90y=1900
x+y=25, x=25-y
55(25-y)+90y=1900
1375-55y+90y=1900
35y=525
y=15
So it is 15 for the 90$ and 10 for the 55$