Concept explainers
PROBLEMS
Distance, Time, and Speed An old car has to travel a 2-mile route, uphill and down .Because it is so old, the car can climb the first mile-the ascent-no faster than an average speed of 15mi/h. How fast does the car to travel the second mile-on the descent it can go faster, of course-to achieve an average speed of 30 mi/h for the trip?
To find:
An old car travel has to travel a 2-mie route, uphill and down. The car can climb the first mile-the ascent-no faster than an average speed of 15 mi/h. How fast does the car have to travel the second mile on the descent it can go faster to achieve an average speed of 30 mi/h for the trip.
Answer to Problem 1P
Solution:
It can’t go fast enough.
Explanation of Solution
Calculation:
The speed of the car when the man drives from home to work=50mi/h.
The speed of the car when the man drives from work to home=30mi/h.
The total distance travelled by the man is
That is,
Then the total time taken for the journey is
To find the average speed of the man during his entire trip.
It can’t go fast enough. Because it exceeds the average speed limit.
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Chapter PL Solutions
Student Solutions Manual for Stewart/Redlin/Watson's Algebra and Trigonometry, 4th
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