29.The distance from Seattle, Washington, to Victoria, British Columbia, is about 148 mi
by ferry. It takes about 4 hr less to travel by the same ferry from Victoria to Vancouver,
British Columbia, a distance of about 74 mi. What is the average rate of the ferry?30.Driving from Tulsa to Detroit, Dean Loring averaged 50 mph. He figured that if he had
averaged 60 mph, his driving time would have decreased 3 hr. How far is it from Tulsa to
Detroit?Concept Check Solve each problem.
31.If it takes Elayn 10 hr to do a job, what is her rate?
32.If it takes Clay 12 hr to do a job, how much of the job does he do in 8 hr?In Exercises 33 and 34, set up the equation you would use to solve each problem. Do not
actually solve the equation. See Example 3.474 CHAPTER 7 Rational Expressions and Applications
British Columbia
Washington
VictoriaVancouverSeattle148 mi74 mi33.Working alone, Edward Good can paint
a room in 8 hr. Abdalla Elusta can paint
the same room working alone in 6 hr.
How long will it take them if they work
together? (Let trepresent the time they
work together.)34.Donald Bridgewater can tune up his
Chevy in 2 hr working alone. Jeff
Bresner can do the job in 3 hr working
alone. How long would it take them if
they worked together? (Let trepresent
the time they work together.)rtw
Edward t
Abdalla trtw
Donald t
Jeff tSolve each problem. See Example 3.
35.Heather Schaefer, a high school mathematics teacher, gave a test on perimeter, area, and
volume to her geometry classes. Working alone, it would take her 4 hr to grade the tests.
Her student teacher, Courtney Slade, would take 6 hr to grade the same tests. How long
would it take them to grade these tests if they work together?
36.Zachary and Samuel are brothers who share a bedroom. By himself, Zachary can com-
pletely mess up their room in 20 min, while it would take Samuel only 12 min to do the
same thing. How long would it take them to mess up the room together?
37.A pump can pump the water out of a flooded basement in 10 hr. A smaller pump takes
12 hr. How long would it take to pump the water from the basement with both pumps?
38.Lou Viggiano’s copier can do a printing job in 7 hr. Nora Demosthenes’ copier can do the
same job in 12 hr. How long would it take to do the job with both copiers?
39.An experienced employee can enter tax data into a computer twice as fast as a new em-
ployee. Working together, it takes the employees 2 hr. How long would it take the experi-
enced employee working alone?
40.One roofer can put a new roof on a house three times faster than another. Working to-
gether, they can roof a house in 4 days. How long would it take the faster roofer working
alone?http://www.ebook777.com
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