Maths question

[Kira]

Sorry.... forget to change that...

;p

 

[tamade]

Thanks all for the help

 

[licorx]

my solution...

6 men can do the job in 96 hours, therefore 1 man can do it in 6x96=576 hours

9 women can do the same job in 166.2 hours, therefore 1 woman can do it in 9x166.2=1495.8 hours

1/576 --> the fraction of the job that 1 man can do in 1 hour

2 x (1/576) --> the fraction of the job that 2 men can do in 1 hour

1/1495.8 -- the fraction of the job that 1 woman can do in 1 hour

4 x (1/1495.8) --> the fraction of the job that 4 women can do in 1 hour


if h is the total hours that will take 2 men and 4 women to do the job,
then 1/h is the fraction of the job that it will be done by 2-men and 4-women in 1 hour


therefore,

....2/576.............+....4/1495.8.............=.....1/h

....work by 2 men.......work by 4 women.........job done
....in 1 hour...............in 1 hour.....................in 1 hour


simpifying,

2(1495.8)h + 4(576)h = 576(1495.8)

2991.6h + 2304h = 861580.8

5295.6h = 861580.8

solving for h, qed

h = 162.69


hope this helps...