SOLUTION: If sally can paint a house in 4 hours and John can paint the same house in 6 hours, how long will it take for both of them to paint the house?
Solution:
Sally's speed of pain
Algebra ->
Rate-of-work-word-problems
-> SOLUTION: If sally can paint a house in 4 hours and John can paint the same house in 6 hours, how long will it take for both of them to paint the house?
Solution:
Sally's speed of pain
Log On
Question 186549: If sally can paint a house in 4 hours and John can paint the same house in 6 hours, how long will it take for both of them to paint the house?
Solution:
Sally's speed of painting the house is 1/4 per hour. John's speed is 1/6 per hour.
Let T = time.
1/4 T +1/6 T =1
(1/4+1/6)T=1
(3/12+_2/12) T=1
5/12 T=1
T=12/5=2 2/5
T=2hours 12 minutes.
Answer: Sally and John can paint the house in 2 hours and 12 minutes. Answer by irkagorska(1) (Show Source):
You can put this solution on YOUR website! We can use the formula: rate x time = 1(job done)
Let T be the time needed for both to paint the house
Sally's rate is 1/4 per hour
John's rate is 1/6 per hour
So : (1/4)T +(1/6)T=1
(3/12+2/12)T=1
(5/12)T=1
T=12/5
12/5 hrs=2hours and 12 minutes.
(