SOLUTION: Can you help me with this problem: It takes Kenny 3 hours to pedal a tamdem bicycle from one end of town to the other. If Dolly pedals with him, they can make the trip in 2 hours.
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-> SOLUTION: Can you help me with this problem: It takes Kenny 3 hours to pedal a tamdem bicycle from one end of town to the other. If Dolly pedals with him, they can make the trip in 2 hours.
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Question 177627: Can you help me with this problem: It takes Kenny 3 hours to pedal a tamdem bicycle from one end of town to the other. If Dolly pedals with him, they can make the trip in 2 hours. How long would it take Dolly to travel from one end to the other alone. Answer by ptaylor(2198) (Show Source):
You can put this solution on YOUR website! Although this appears to be a travel word problem, it's actually a rate-of-work problem where the complete job is travelling from one end of town to the other.
Let x=amount of time it takes Dolly alone to pedal from one end of town to the other
So Dolly pedals at the rate of 1/x of the distance from one end of the town to the other per hour
Kenny pedals at the rate of 1/3 of the distance from one end of town to the other per hour
Dolly & Kenny together pedals at the rate of 1/2 of the distance from one end of town to the other per hour
So our equation to solve is:
1/3 + 1/x = 1/2 multiply each term by 6x
2x+6=3x subtract 2x from each side
3x-2x=2x-2x+6 or
x=6 hours time for dolly to travel alone from one end of town to the other
CK
1/3 +1/6 = 1/2
2/6+1/6=1/2
1/2=1/2
