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

(1) If Nancy can finish the work in 25 days and Ronald can finish the same work in 29 days, then in how many days both can finish the work together?

(2) Brian can finish a work in 45 days. George can finish the same work in 46 days while Timothy can finish the work in 47 days. How long will it take to finish it if they work together?

(3) Michelle can finish a work in 40 days. Carol can finish the same work in 41 days while Amanda can finish the work in 42 days. How long will it take to finish it if they work together?

(4) If Paul can finish the work in 36 days and Larry can finish the same work in 39 days, then in how many days both can finish the work together?

(5) If Christopher can finish the work in 22 days and Brian can finish the same work in 25 days, then in how many days both can finish the work together?

(6) Jennifer can finish a work in 6 days. Linda can finish the same work in 7 days while Elizabeth can finish the work in 8 days. How long will it take to finish it if they work together?

(7) If Christopher can finish the work in 22 days and Brian can finish the same work in 26 days, then in how many days both can finish the work together?

(8) John can finish a work in 5 days. Michael can finish the same work in 6 days while David can finish the work in 7 days. How long will it take to finish it if they work together?

(9) Matthew can finish a work in 29 days. Mark can finish the same work in 34 days while Donald can finish the work in 39 days. How long will it take to finish it if they work together?

(10) Patricia can finish a work in 4 days. Jennifer can finish the same work in 5 days while Linda can finish the work in 6 days. How long will it take to finish it if they work together?


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