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What formula is used to determine If sally cfan paint a house in four hours and john can paint the same house in 6 hours how long will it take for both of them to paint the house together?
Wiki User
∙ 12y ago
You don't need a formula. You need to understand where the answer comes from.
If you understand where the answer comes from, you can write your own formula.
If you don't, then a formula can be dangerous in your hands.
-- Sally can paint 1/4 of the house in an hour.
-- John can paint 1/6 of the same house in an hour.
-- If they work together, then can paint (1/4 + 1/6) = 5/12 of the house in an hour.
-- If they paint 5/12 of the house in an hour, then it takes them 12/5 hours to
finish the job, or 2.4 hours, or 2hours 24minutes.
Well, OK. Here's the formula:
S = number of hours it takes Sally
J = number of hours it takes John
Number of hours it takes them working together = 1 / (1/S + 1/J)
Wiki User
∙ 12y ago
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It takes Sal 5 hours to paint a house It takes Sal 3 hours to paint the same house How long will it take to paint the house if both of them work together?
It would take them 4 hours to paint the house together.
If it takes a person 5 hours to wash a house and another person 3 hours how long does it take them to both wash the house together?
Less than two hours.
Jane needs 3 hours to clean the Smith house Her younger sister Alice can clean the house in 5 hours How long would the sisters working together need to clean the house?
~1.9 hours
Juan accepted a job to roof a new house He can complete the job in 20 hours His trainee takes 25 hours to complete the job How much time should the two of them working together need to roof the house?
It will take about 11.1 hours for the two of them to complete the roofing of the house.
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 of them to paint the house together?
Sally does a quarter of the house in an hour, John does one-sixth, so together they would do 5/12 in an hour, thus it would take 12/5 hours ie 2 hrs 24 min in theory. In practice, because of arguments it would probably take three hours plus!
It takes Sal 5 hours to paint a house It takes Sal 3 hours to paint the same house How long will it take to paint the house if both of them work together?
It would take them 4 hours to paint the house together.
If it takes a person 5 hours to wash a house and another person 3 hours how long does it take them to both wash the house together?
Less than two hours.
Jane needs 3 hours to clean the Smith house Her younger sister Alice can clean the house in 5 hours How long would the sisters working together need to clean the house?
~1.9 hours
How do you translate a word phrase into a math expression?
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 them to paint the house together?
If john can paint a house in 5 hours and joe can paint a house in 3 hours how long will it take for both of them to paint the house?
The way you calculate this (assuming that both work at constant speed) is:* Calculate what part of the house each person can paint in an hour. * Add both fractions together, to calculate what part of the house you can paint together. * Take the reciprocal of this last result, to calculate the number of hours.
Juan accepted a job to roof a new house He can complete the job in 20 hours His trainee takes 25 hours to complete the job How much time should the two of them working together need to roof the house?
It will take about 11.1 hours for the two of them to complete the roofing of the house.
If a roofing contractor estimates that he can shingle a house in twenty hours and that his assistant can do it in thirty hours how long will it take them to shingle the house working together?
About 12.5 hours if they just work. Since there are now two people working, the gab factor could increase that to 40 hours.
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 of them to paint the house together?
Sally does a quarter of the house in an hour, John does one-sixth, so together they would do 5/12 in an hour, thus it would take 12/5 hours ie 2 hrs 24 min in theory. In practice, because of arguments it would probably take three hours plus!
If sally can paint a house in four hours and john can paint the same house in 6 hours how long will it take for both of them to paint the house together?
Sally does 1 job in 4 hours ===> 1/4th of the job per hour.John does 1 job in 6 hours ===> 1/6th of the job per hour.Working together, they do (1/4 + 1/6) = (3/12 + 2/12) = 5/12 job per hour.The job takes 12/5 = 2.4 hours = 2hours24minutes to complete.
If sally can paint a house in four hours and john can paint the same house in 6 hours how long will it take both of them to paint the house?
In one hour Sally paints one quarter and John paints one sixth, between them they paint five twelfths per hour so would take 2 hours 24 minutes if they worked together. But have you ever known a male and a female to work harmoniously together? Allow at least three hours!
If Joe can paint a house in 3 hours and Sam can paint the same house in 5 hours how long does it take for them to do it together?
Joe can paint the house in 3 hours so Joe paints 1/3 house in an hour. Similarly, Sam paint 1/5 of the house in one hour. So together (assuming no synergy) they paint 1/3 + 1/5 = 8/15 of the house in an hour. So they take 15/8 = 1 + 7/8 = 1.875 days to paint it.
When was After Hours at the London House created?
After Hours at the London House was created in 1959.
