I have a couple questions regarding the work problems below. I know how to solve these through plugging in numbers or using the answer choices, but how would you solve these algebraically?
1.Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?
2. A pool can be filled in 4 hours and drained in 5 hours. The valve that fills the pool was opened at 1:00 pm and some time later the drain that empties the pool was also opened. If the pool was filled by 11:00 pm and not earlier, when was the drain opened?
a. at 2:00 pm
b. at 2:30 pm
c. at 3:00 pm
d. at 3:30 pm
e. at 4:00 pm
3.It takes printer A 4 more minutes than printer B to print 40 pages. Working together, the two printers can print 50 pages in 6 minutes. How long will it take printer A to print 80 pages?
I think you should have posted all these questions in separate threads. Anyways, I will take a stab at the first question:
A + B --> 24 minutes
A = p / min
B = p + 5 / min
A + B will both produce pages in 24 minutes = 24p + 24(p+5) = 48p + 120
Total pages = 60p (As it takes A 60 minutes to finish the task)
48p + 120 = 60p
Total pages = 10*60 = 600
press kudos, if you like the explanation, appreciate the effort or encourage people to respond.
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