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 Carol can finish the work in 46 days and Alexander can finish the same work in 51 days, then in how many days both can finish the work together?

(2) If Joseph can finish the work in 16 days and Steven can finish the same work in 20 days, then in how many days both can finish the work together?

(3) If Steven can finish the work in 34 days and Jonathan can finish the same work in 38 days, then in how many days both can finish the work together?

(4) If George can finish the work in 48 days and Dennis can finish the same work in 51 days, then in how many days both can finish the work together?

(5) If Joseph can finish the work in 16 days and Steven can finish the same work in 19 days, then in how many days both can finish the work together?

(6) Ashley can finish a work in 36 days. Emily can finish the same work in 41 days while Donna can finish the work in 46 days. How long will it take to finish it if they work together?

(7) If James can finish the work in 24 days and John can finish the same work in 40 days, then in how many days both can finish the work together?

(8) If Scott can finish the work in 81 days and Bryan can finish the same work in 86 days, then in how many days both can finish the work together?

(9) If A can do a piece of work in 2 days, B can do the same piece of work in 3 days, while C alone can do the same work in 4 days. Find the number of days to finish the work when they all will work together.

(10) Catherine can finish a work in 100 days. Heather can finish the same work in 105 days while Diane can finish the work in 110 days. How long will it take to finish it if they work together?


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