Rate problem!

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Rate problem!

by bobdylan » Wed Jun 06, 2012 5:07 am
A boy walking along a road at 3 km/hr is overtaken by a truck traveling at 40 km /hr. If the truck breaks down one km beyond where it passes the boy, how many minutes after the breakdown does the boy reach the truck?
a) 21 1/2 b) 20 c) 18 34/37 d) 18 26/43 e) 18 1/2

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by Ashujain » Wed Jun 06, 2012 5:43 am
bobdylan wrote:A boy walking along a road at 3 km/hr is overtaken by a truck traveling at 40 km /hr. If the truck breaks down one km beyond where it passes the boy, how many minutes after the breakdown does the boy reach the truck?
a) 21 1/2 b) 20 c) 18 34/37 d) 18 26/43 e) 18 1/2
Time taken by truck to travel 1km = 1/40 hrs = 60/40 mins = 1.5 mins
Time taken by boy to travel 1km = 1/3 hrs = 60/3 mins = 20 mins
Therefore, the boy will reach the truck in 20-1.5 = 18.5 mins [spoiler](E)[/spoiler]

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by amit28it » Sat Jun 09, 2012 12:15 am
In my opinion the solution provided by Ashujain is good and here is mine
First of all,
The Time taken by truck to travel a km = 1/40 hrs = 60/40 mins = 1.5 mins
Time taken by the boy to travel 1km = 1/3 hrs = 60/3 mins = 20 mins
Therefore, the boy will reach the truck in 20 - 1.5 = 18.5 mins
This is the simplest method I think.
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