Question

(30 POINTS!!!) One press can run the day’s newspapers in 6 hours, while another can do the same job in 8 hours. After running together for 2 hours to complete the job, the faster one breaks. How much longer must the slower press run to finish the newspapers?

Answer 1

Amount of the job done after 2 hours:

2(1/6 + 1/8)

2(4/24 + 3/24)

2(7/24)

7/12 (amount of job finished)

.

amount of job left to do:

1 - 7/12

 

12/12 - 7/12

5/12 (remaining)

.

Let x = time (hours) slower press takes to finish job

then

x(1/6) = 5/12

multiplying both sides by 6:

x = 5/12 *6

x = 5/2 hours

or

x = 2 hours and 30 minutes

The slower press (8-hour press), will take h 3 hours, 20 minutes to complete the job