Mow a lawn Puzzle | 28 Jun 2009

Discussion in '\$1 Daily Competition' started by shabbir, Jun 28, 2009.

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"A" can mow a lawn in 2 hours while "B" can do so in 2.5 hours separately. If A & B work together, how long will it take for them to mow the lawn?

2. mayjuneNew Member

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Ans is 1.112 hours (aprox)

Lets say the lawn is 1000 sq mts
A takes 1000/120 mins i.e. in one min = 8.334 mts
B takes 1000/150 mins i.e. in one min = 6.667 mts
Total time = x
6.66x + 8.33x = 1000
x = 66.67 (aprox)
Therefore 1.112 hours (aprox)

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In 1 hour, A can mow 1/2 the lawn.
In 1 hour, B can mow 2/5 of the lawn.
Together in 1 hour, they can mow 1/2 + 2/5 = 9/10 of the lawn.
So to complete the lawn mowing, it will take them 10/9 hours.

Its rare we have a Winner before a post from Saswat

4. SaswatPadhi~ Б0ЯИ Τ0 С0δЭ ~

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Actually, I have already reached the limit : 3 wins/week. So I was not actually waiting for Today's puzzle.

Congrats mayjune.

5. mayjuneNew Member

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donate my 1\$ to the open source please...

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Will do that. And as always if you have any open source projects please do let me know.

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