SOLUTION: Few workers are appointed to dig up a trench. They start at an elevation of 3 1/2 feet. The workers dig for 2 1/2 hours at a rate of 3 1/4 feet per hour. For the next 4 1/2 hours,

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Question 983080: Few workers are appointed to dig up a trench. They start at an elevation of 3 1/2 feet. The workers dig for 2 1/2 hours at a rate of 3 1/4 feet per hour. For the next 4 1/2 hours, the workers dig at a rate of 2 5/6 feet per hour. Then the workers stop for the day.
How many feet do the workers dig after 2 1/2 hours?
What is the elevation of the bottom of the trench at the end of the day?
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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First part of the day:
(2.5hrs)(3.25ft/hr)=8.125 feet
ANSWER 1: They dig 8.125 feet in 2.5 hours.
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Second part of day:
(4.5hrs)(2.83ft/hr)=12.75feet
They dig 12.75 feet during the second part of the day.
For the entire day, they dig 8.125ft+12.75ft=20.875 feet.
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Since they started at elevation 3.5 feet, at the end of the day the bottom of the trench is at 3.5 feet-20.875 feet=-17.375 feet
ANSWER 2: At the end of the day, the bottom of the trench is at elevation -17.375 feet.