Time and Work
MCQs Math


Question:     If Stephanie can finish the work in 56 days and Adam can finish the same work in 61 days, then in how many days both can finish the work together?


Correct Answer  29 23/117 days or 29.197 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Stephanie = 56 days

And, the number of days to finish the same work by Adam = 61 days

Thus, the number of days to finish the work by Stephanie and Adam together = ?

Here,

∵ In 56 days the work done by Stephanie = 1

∴ In 1 day, the work done by Stephanie = 1/56 part

Similarly,

∵ In 61 days the work done by Adam = 1

∴ In 1 day, the work done by Adam = 1/61 part

Now, in 1 day, the work done by Stephanie and Adam together

= In 1 day work done by Stephanie + In 1 day the work done by Adam

= 1/56 + 1/61

= 61 + 56/3416

= 117/3416 part of work

This means in 1 day, 117/3416 part of work is done by Stephanie and Adam working together.

Now, the number of days required to finish 117/3416 part of work by Stephanie + Adam working together = 1

∴ the number of days required to finish 1 work by Stephanie + Adam together

= 1/117/3416

= 1 × 3416/117 = 3416/117 days

= 29 23/117 days = or 29.197 days

Thus, Stephanie and Adam working together will finish the work in 29 23/117 days = or 29.197 days Answer

Shortcut Trick to solve the problems based on time and work using formula

Case: If A can finish a work in a days, and B can finish the same work in b days,
then working together the number of days require to finish the work
= a × b/a + b days.

Here given,

The number of days required to finish the work by Stephanie = 56 days

And the number of days required to finish the same work by Adam = 61 days

Thus, the number of days required to finish the work Stephanie and Adam working together = ?

Here a = 56 days

And, b = 61 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Stephanie and Adam working together

= 56 × 61/56 + 61 days

= 3416/117 days

= 29 23/117 days or 29.197

Thus, Stephanie and Adam together will finish the work in 29 23/117 days or 29.197 days Answer


Similar Questions

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(2) If George can finish the work in 51 days and Dennis can finish the same work in 56 days, then in how many days both can finish the work together?

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