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

(1) Amy can finish a work in 68 days. Shirley can finish the same work in 73 days while Anna can finish the work in 78 days. How long will it take to finish it if they work together?

(2) If David can finish the work in 10 days and Christopher can finish the same work in 13 days, then in how many days both can finish the work together?

(3) If Linda can finish the work in 9 days and Charles can finish the same work in 13 days, then in how many days both can finish the work together?

(4) Jennifer can finish a work in 10 days. Elizabeth can finish the same work in 15 days while Barbara can finish the work in 20 days. How long will it take to finish it if they work together?

(5) Joshua can finish a work in 43 days. Kevin can finish the same work in 48 days while Brian can finish the work in 53 days. How long will it take to finish it if they work together?

(6) If Amanda can finish the work in 48 days and Patrick can finish the same work in 53 days, then in how many days both can finish the work together?

(7) Mark can finish a work in 33 days. Steven can finish the same work in 38 days while Paul can finish the work in 43 days. How long will it take to finish it if they work together?

(8) If Michael can finish the work in 30 days and Thomas can finish the same work in 46 days, then in how many days both can finish the work together?

(9) Samuel can finish a work in 87 days. Alexander can finish the same work in 92 days while Frank can finish the work in 97 days. How long will it take to finish it if they work together?

(10) If Jeffrey can finish the work in 61 days and Peter can finish the same work in 66 days, then in how many days both can finish the work together?


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