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if sarah and tim work together use 4 hours to finish a project, tim use 6 hours to complete the project alone, how long will sarah finish project alone?

1 Answer

3 votes

Answer:

She will finish in 12 hours.

Step-by-step explanation:

∵ The time taken by Sarah and Tim when they work together = 4 hours,

∴ The one day work of both Sarah and Tim =
(1)/(4)

Now, time taken by Tim when he works alone = 6 hours,

So, his one day work =
(1)/(6)

Thus, the one day work of Sarah = Their combined work - one day work of Tim


=(1)/(4)-(1)/(6)


=(3-2)/(12)


=(1)/(12)

Hence, the time taken by Sarah when she works alone =
\frac{1}{\text{her one day work}}


=(1)/(1/12)

= 12 days.

User Jeff Dicket
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