do it together?
2006-10-15 11:57:39 · 13 answers · asked by rhtgrhghhg h 1 in Education & Reference ➔ Homework Help
Well you have to make some assumptions here first, that both Peter's house and John's house are the same size.
So assuming that, then that means Peter can paint 1/2 the house in 1.5 hours, and John can paint 1/2 the house in 2.5 hours. So at the end of 1.5 hours, Peter has painted half the house, and John still has 1 hr to go on his half of the house. So the answer has to be something greater than 1.5 hours, but less than 2.5 hours.
Let's look at it algebraically. Let x be the size of the house. Peter paints x/3 of the house per hour (since it takes him 3 hours to do the whole house), and John paints x/5 of the house per hour (since it takes him 5 hours to do the whole house).
So every hour, together they paint x/3 + x/5 of the house, or 8/15 of the house.
Thus, to paint the whole house, they need to work 15/8 hours (because 15/8 hrs * 8/15 house per hour = 1 house).
15/8 hours = 1 hr 52.5 minutes
2006-10-15 11:59:35 · answer #1 · answered by dualspace 3 · 0⤊ 0⤋
4
2006-10-15 19:00:41 · answer #2 · answered by Corinne S 2 · 0⤊ 0⤋
The total time it took Peter and John to do both of the houses separately was eight hours. Let's assume that Peter's house was 3000 square feet and John's 5000 square feet and they both painted 1000 square feet per hour. They therefore would paint at the speed of 2000 square feet per hour when working together and would finish the 8000 square feet of both houses in 4 hours.
2006-10-15 19:43:47 · answer #3 · answered by Marv-ink 1 · 0⤊ 0⤋
4 hours because peter's house took him 3 hrs to paint so if there are two people to help it would take 1.5 hrs and john's house took him 5 hrs and with 2 peole it would also take half the time which would be 2.5 hrs so 2.5 +1.5 =4
so you can conclude peter's house is smaller than john's house.
2006-10-15 19:20:29 · answer #4 · answered by Anonymous · 0⤊ 0⤋
to do what??
paint one house 2hours
paint 2 houses 4 hours
paint johns house. 1 hour(this is all theoretical. john paints 2.3 times slower than peter, and he has a smaller house, so if they worked togethre, it would only take 58.5 minutes
piant peters house 2hours(peters house is twice as big as johns, and they run out of paint twice and have to drive to teh city
2006-10-15 19:02:26 · answer #5 · answered by §@mM¥ 2 · 0⤊ 0⤋
4 hours
2006-10-15 19:02:34 · answer #6 · answered by bob_whelan1944 3 · 0⤊ 1⤋
8 hours
2006-10-15 19:01:09 · answer #7 · answered by ash 4 · 0⤊ 1⤋
probably 4. i think it's four because maybe you'll need to find the average of both of them together. 5+3=8. 8 divided by 2= 4
2006-10-15 19:01:17 · answer #8 · answered by mocool13 2 · 0⤊ 0⤋
It depends on how many beers they have in between breaks. And who can paint a whole house in 3 hours by himself?
2006-10-15 19:05:13 · answer #9 · answered by DikkiJones 3 · 0⤊ 1⤋
2 hours?
2006-10-15 18:59:39 · answer #10 · answered by ♪~♥~♫~♥~♪ 3 · 0⤊ 0⤋