When Sandy and Allen’s mother decorates the house for a holiday by herself, it takes her 5 hours. When both Sandy and Allen help, the three

Question

When Sandy and Allen’s mother decorates the house for a holiday by herself, it takes her 5 hours. When both Sandy and Allen help, the three can finish the job in 2.5 hours. When only Allen helps his mother decorate, it takes the two 3.5 hours. How long would it take Sandy to decorate the house by herself?

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Minh Khuê 6 months 2021-07-21T02:08:44+00:00 2 Answers 2 views 0

Answers ( )

    0
    2021-07-21T02:09:50+00:00

    Answer:

    8 3/4

    Step-by-step explanation:

    time for all work:

    Mother – 5 hours

    Mother + Sandy + Allen – 2.5 hours

    Mother + Allen – 3.5 hours

    Sandy – x

    In 1 hour

    Mother – 1/5

    Mother + Sandy + Allen – 2/5

    Mother + Allen – 2/7

    Sandy – 1/x

    (M+S+A) – S = (M+A)

    2/5 – 1/x = 2/7

    solve equation

    x = 8 3/4 hours

    Hope this helps 🙂

    0
    2021-07-21T02:10:05+00:00

    Answer:

    5 hours

    Step-by-step explanation:

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