SOLUTION: The larger of printing presses can print a job in four hours. If both presses together, they can print the same job in two hours and 24 minutes. How long would it take the smaller

Algebra ->  Rate-of-work-word-problems -> SOLUTION: The larger of printing presses can print a job in four hours. If both presses together, they can print the same job in two hours and 24 minutes. How long would it take the smaller       Log On


   

Question 915620: The larger of printing presses can print a job in four hours. If both presses together, they can print the same job in two hours and 24 minutes. How long would it take the smaller press to print the job alone?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add their rates of printing to find
their rate printing together
+24+ min = +2%2F5+ hrs
+2+=+10%2F5+ hrs
+1%2F4+%2B+1%2Ft+=+1%2F%28%2812%2F5%29%29+
+1%2F4+%2B+1%2Ft+=+5%2F12+
Multiply both sides by +12t+
+3t+%2B+12+=+5t+
+2t+=+12+
+t+=+6+
The smaller press prints the job in 6 hrs
check:
+1%2F4+%2B+1%2F6+=+5%2F12+
+3%2F12+%2B+2%2F12+=+5%2F12+
+5%2F12+=+5%2F12+
OK