Time and Work
MCQs Math


Question:     If Margaret can finish the work in 29 days and Ryan can finish the same work in 32 days, then in how many days both can finish the work together?


Correct Answer  15 13/61 days or 15.213 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Margaret = 29 days

And, the number of days to finish the same work by Ryan = 32 days

Thus, the number of days to finish the work by Margaret and Ryan together = ?

Here,

∵ In 29 days the work done by Margaret = 1

∴ In 1 day, the work done by Margaret = 1/29 part

Similarly,

∵ In 32 days the work done by Ryan = 1

∴ In 1 day, the work done by Ryan = 1/32 part

Now, in 1 day, the work done by Margaret and Ryan together

= In 1 day work done by Margaret + In 1 day the work done by Ryan

= 1/29 + 1/32

= 32 + 29/928

= 61/928 part of work

This means in 1 day, 61/928 part of work is done by Margaret and Ryan working together.

Now, the number of days required to finish 61/928 part of work by Margaret + Ryan working together = 1

∴ the number of days required to finish 1 work by Margaret + Ryan together

= 1/61/928

= 1 × 928/61 = 928/61 days

= 15 13/61 days = or 15.213 days

Thus, Margaret and Ryan working together will finish the work in 15 13/61 days = or 15.213 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 Margaret = 29 days

And the number of days required to finish the same work by Ryan = 32 days

Thus, the number of days required to finish the work Margaret and Ryan working together = ?

Here a = 29 days

And, b = 32 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Margaret and Ryan working together

= 29 × 32/29 + 32 days

= 928/61 days

= 15 13/61 days or 15.213

Thus, Margaret and Ryan together will finish the work in 15 13/61 days or 15.213 days Answer


Similar Questions

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(2) If Richard can finish the work in 36 days and Mark can finish the same work in 52 days, then in how many days both can finish the work together?

(3) If Annie can finish a work in 5 days and Bobby can finish the same work in 10 days, then in how many days they both can finish the work working together?

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(6) If Rachel can finish the work in 94 days and Roy can finish the same work in 99 days, then in how many days both can finish the work together?

(7) Dorothy can finish a work in 46 days. Melissa can finish the same work in 47 days while Deborah can finish the work in 48 days. How long will it take to finish it if they work together?

(8) If Elizabeth can finish the work in 11 days and Daniel can finish the same work in 14 days, then in how many days both can finish the work together?

(9) If Ryan can finish the work in 63 days and Ethan can finish the same work in 68 days, then in how many days both can finish the work together?

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