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?
2007-04-22 04:33:40 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Sally paints 1/4 of the house in 1 hr.
John paints 1/6 of the house in 1 hr.
Together they paint 1/4 + 1/6 = (3 + 2)/12 = 5/12 of the house in 1hr.
To paint the whole house, they take 12/5 = 2 2/5 hr.
= 2hr 24min.
2007-04-22 04:39:31 · answer #1 · answered by Anonymous · 3⤊ 0⤋
Figure how much each can do in 1 hour.
(Of course, assume a uniform work rate!)
Sally can paint 1/4 of the house in 1 hour
and John can paint 1/6 of it in 1 hour.
Together they can paint
1/4 + 1/6 = 1/x of it in 1 hour.
So 1/x = 1/4 + 1/6 = 5/12
x = 12/5 hours = 2 hours 24 minutes.
2007-04-22 12:19:55 · answer #2 · answered by steiner1745 7 · 0⤊ 0⤋
5 hours , Sally paints half (2 hours) and John paints half (3 hours)
2007-04-22 11:45:50 · answer #3 · answered by nixsta_21 1 · 0⤊ 1⤋
Well sally started at the same time John did and when she was done with her half ,she noticed that the slacker was only 2/3 of the way done with his half,So she left and went to the bar and waited an hour for John to finish his half.
2007-04-22 11:42:49 · answer #4 · answered by nmatkozich@verizon.net 1 · 0⤊ 1⤋
5 hours. 6 hours + 4 hours = 10 hours.
Half of 10 hours = 5 hours.
2007-04-22 11:49:31 · answer #5 · answered by Anonymous · 0⤊ 1⤋
That will be 2.4 Hours
2007-04-22 11:43:48 · answer #6 · answered by Me 4 · 0⤊ 0⤋
2.25hr
2007-04-22 11:40:33 · answer #7 · answered by dwinbaycity 5 · 1⤊ 2⤋