Time and Work
MCQs Math


Question:     If Karen can finish the work in 24 days and Kevin can finish the same work in 29 days, then in how many days both can finish the work together?


Correct Answer  13 7/53 days or 13.132 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Karen = 24 days

And, the number of days to finish the same work by Kevin = 29 days

Thus, the number of days to finish the work by Karen and Kevin together = ?

Here,

∵ In 24 days the work done by Karen = 1

∴ In 1 day, the work done by Karen = 1/24 part

Similarly,

∵ In 29 days the work done by Kevin = 1

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

Now, in 1 day, the work done by Karen and Kevin together

= In 1 day work done by Karen + In 1 day the work done by Kevin

= 1/24 + 1/29

= 29 + 24/696

= 53/696 part of work

This means in 1 day, 53/696 part of work is done by Karen and Kevin working together.

Now, the number of days required to finish 53/696 part of work by Karen + Kevin working together = 1

∴ the number of days required to finish 1 work by Karen + Kevin together

= 1/53/696

= 1 × 696/53 = 696/53 days

= 13 7/53 days = or 13.132 days

Thus, Karen and Kevin working together will finish the work in 13 7/53 days = or 13.132 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 Karen = 24 days

And the number of days required to finish the same work by Kevin = 29 days

Thus, the number of days required to finish the work Karen and Kevin working together = ?

Here a = 24 days

And, b = 29 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Karen and Kevin working together

= 24 × 29/24 + 29 days

= 696/53 days

= 13 7/53 days or 13.132

Thus, Karen and Kevin together will finish the work in 13 7/53 days or 13.132 days Answer


Similar Questions

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(2) If Barbara can finish the work in 13 days and Anthony can finish the same work in 16 days, then in how many days both can finish the work together?

(3) If Annie can finish a work in 2 days and Bobby can finish the same work in 3 days, then in how many days they both can finish the work working together?

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(6) If Anna can finish the work in 74 days and Austin can finish the same work in 79 days, then in how many days both can finish the work together?

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(8) If Steven can finish the work in 37 days and Jonathan can finish the same work in 42 days, then in how many days both can finish the work together?

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