Re: Help - simple algebra

In article <O_BEj.14454$jH5.8429@[EMAIL PROTECTED]
>,
 Martin <martin.wilkins50@[EMAIL PROTECTED]
> wrote:

> How do you solve this problem
> 
> If Sally can paint a house in 4 hours, and John can paint the same house

> in 6 hour, how long will it take for both of them to paint the house 
> together?
> 
> 	2 hours and 24 minutes
> 	3 hours and 12 minutes
> 	3 hours and 44 minutes
> 	4 hours and 10 minutes
> 	4 hours and 33 minutes
> 
> Apparently it's 2 hours and 24 minutes
> 
> Thanks
> 
> Martin

Sally paints 1/x of the house per hour and John paints 1/6 of it per 
hour.

Together they paint 1/4 + 1/6 = 5/12 of the house per hour,
so it takes them 12/5 hours, or 2 hours and 2/5 of another hour,
to paint the house.