Question 351005: Ornery and sly company has a contract to dig a tunnel though bald mountain. Crew A start at the west end and digs at 9 meters per day . Let X be the number of days Crew A has been digging . Crew B starts at the east end two days after Crew A and digs at 12 meters per day.
a. show rate, tme and distance each crew has dug.
b. after how many days will the crews have dug the same distance?
c. The total length of the tunnel is to be 2000 meters . write an equation stating this fact. Then solve the equation to find out how many days it takes to dig the tunnel from the time Crew A starts.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Ornery and sly company has a contract to dig a tunnel though bald mountain.
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Crew A start at the west end and digs at 9 meters per day . Let X be the number of days Crew A has been digging .
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show rate, tme and distance each crew has dug.
distanceA = 9x meters
time = x days
rate = 9 meters per day
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Crew B starts at the east end two days after Crew A and digs at 12 meters per day.
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show rate, tme and distance each crew has dug.
distanceB = 12(x-2) = 12x-24 meters
time = x-2 days
rate = 12 meters per day
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b. after how many days will the crews have dug the same distance?
Solve 9x = 12x-24
3x = 24
x = 8 days
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c. The total length of the tunnel is to be 2000 meters . write an equation stating this fact. Then solve the equation to find out how many days it takes to dig the tunnel from the time Crew A starts.
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Equation:
distanceA + distanceB = 2000
9x + 12x-24 = 2000
21x = 2024
x = 96.38 days
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Cheers,
Stan H.
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