Mow a lawn Puzzle  28 Jun 2009
"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?

Re: Mow a lawn Puzzle  28 Jun 2009
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) 
Re: Mow a lawn Puzzle  28 Jun 2009
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 :D 
Re: Mow a lawn Puzzle  28 Jun 2009
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Congrats mayjune. 
Re: Mow a lawn Puzzle  28 Jun 2009
donate my 1$ to the open source please...

Re: Mow a lawn Puzzle  28 Jun 2009
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Re: Mow a lawn Puzzle  28 Jun 2009
will do...

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