Problema Solution

One printing machine works twice as fast as another. When both machines are used, they can print a magazine in 3 h. How many hours would each machine require to do the job alone?

Answer provided by our tutors

first priniting machine needs x hours and second needs 2x hours.

so,

1/x +1/2x = 3/2x

so, total hours 2x/3.

2x/3 = 3

x= 9/2 hours.

so, one machine needs 9/2 hours and second needs 9 hours.