Please help me to solve this?how long will it take for both of them to paint the house together?

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?

PLEASE HELP!

10 Answers

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  • Pranil
    Lv 7
    1 decade ago
    Favorite Answer

    Sally in 4 hours, and John in 6 hour

    calculate the work done by them in 1 hour

    Sally in 4 hours, in 1 hour 1/4 part of work done

    John in 6 hour in 1 hour 1/6 part of work done

    total work done in 1 hour = 1/4 + 1/6 LCM 12

    total work done in 1 hour = 3/12 + 2/12

    = 5/12

    so 5/12 part of work requires 1 hour

    then 1 full work requires 1 ÷ 5/12 hours

    = 12/5 hours

    = 2 2/5 hours

    2/5 hours = 2/5 × 60 = 24 minutes

    Time required for both of them = 2 hours 24 minutes.

  • 1 decade ago

    Sally paints 1/4 house in an hour

    John paints 1/6 house in an hour

    S + J paint 1/4 + 1/6 = 5/12 house in an hour

    So S + J can paint a house in 12/5 hours = 2 2/5 hours = 2 hr 24 min

  • Joel L
    Lv 6
    1 decade ago

    Sally paints 1/4 house in an hour

    John paints 1/6 house in an hour

    S + J paint 1/4 + 1/6 = 5/12 house in an hour

    So S + J can paint a house in 12/5 hours = 2 2/5 hours = 2 hr 24 min

  • 1 decade ago

    Sally paints the house in 4 hours, therefore she is painting 1/4 of the house per hour. John paints the house in 6 hours, therefore he is painting 1/6 of the house per hour.

    In one hour they can both paint 1/4 + 1/6 of the house, common denominator of 12 -> 3/12 + 2/12 = 5/12 of the house per hour.

    So it will take 12/5 of an hour to paint the whole house = 2 2/5 = 2.4 hours = 2 hours 24 minutes.

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  • ?
    Lv 7
    1 decade ago

    Let x=number of hours it takes to do the job together

    1/4 + 1/6 = 1/x

    x=24/10=2.4 hrs

  • 1 decade ago

    let x be the number of hours that it takes for them to paint the house together.

    x/4 + x/6 = 1

    find the common denominator, and this should become a regular equation that solves for x.

    The answer I got is 12/5 hours, or 2.4 hours.

  • Anonymous
    1 decade ago

    Is the painting to be done with a single brush one by one, or both persons paint on the same spot at once together?

  • 1 decade ago

    x/4 + x/6 = 1

    3x + 2x = 12

    5x = 12

    x = 12/5

    Answer: 12/5 hrs or 2.4 hrs or (2 hrs, 24 min)

  • koers
    Lv 4
    4 years ago

    i could recommend blue or eco-friendly (esp. "sage eco-friendly" - this is not distinctly used in hospitals via twist of destiny). study skill that persons have a tendency to discover those colours the main relaxing and calming, distinctly human beings from "western" cultures. there is likewise study suggesting, if i'm remembering my reading in this subject depend out of severe boredom and interest years in the past properly, that blue colours mildly develop productiveness for specific initiatives. Given what you're reading, you're able to discover it thrilling to do a evaluation of the "we painted rooms and..." literature, haha. portray a room with vertical stripes of alternating color on a wall, or 2, or paining one wall a lighter color than the others, could reason rooms to be perceived as extra spacious and open than they could fairly be. this could be suitable if the room is smaller, or if the inflow of recent (probably greater) furniture than in the past makes the room experience smaller. i ought to attempt to offer concepts on a stylistic be conscious, yet in accordance to each and all the ladies human beings in my life, distinctly in accordance my little sister, I truly have a terrible eye for such issues, so it in all probability does not be efficient. reliable success!

  • Anonymous
    1 decade ago

    It will take 2 hrs and 24 minutes.

    If you want to know how I reached the answer, just ask me please.

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