Ind maths question - can anyone suggest an easy method

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teacher_mum
Posts: 10
Joined: Sat May 28, 2011 3:26 pm

Ind maths question - can anyone suggest an easy method

Post by teacher_mum »

Hello All

Can anyone out there suggest an easy method for the following question please ?

It takes 2 decorators 8 days to paint a house. One is lazy and one is energetic. The energetic one could paint the house in 12 days on his own. How many days would it take the lazy one to paint the house on his own ?

My answer is 24 days - but that was doing it using algebra.

If anyone could suggest a simpler way, it would much appreciated.

Many thanks :)
hermanmunster
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Joined: Fri Sep 15, 2006 9:51 am
Location: The Seaside

Re: Ind maths question - can anyone suggest an easy method

Post by hermanmunster »

teacher_mum wrote:Hello All

Can anyone out there suggest an easy method for the following question please ?

It takes 2 decorators 8 days to paint a house. One is lazy and one is energetic. The energetic one could paint the house in 12 days on his own. How many days would it take the lazy one to paint the house on his own ?

My answer is 24 days - but that was doing it using algebra.

If anyone could suggest a simpler way, it would much appreciated.

Many thanks :)

I am no teacher or mathematician - suppose my answer is a bit algebraic but more of a "talk through"

Painter A (the energetic one) can paint 1/12 of a house in one day.
So in 8 days he paints 8/12 or 2/3 or the house.
Meaning jolly painter B has painted 1/3 in 8 days... (maybe he makes the tea?)
so painter B would take 8 times 3 or 24 days to do the lot..

................by which time you would be fed up with him and he have gone off to help his mate on an urgent job half way through.... :twisted:
teacher_mum
Posts: 10
Joined: Sat May 28, 2011 3:26 pm

Re: Ind maths question - can anyone suggest an easy method

Post by teacher_mum »

Hello

Thank you very much for your method - I like the your "cup of tea" method compared to my way of let's make it x

thanks again :)
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