Time and Work
MCQs Math


Question:     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?


Correct Answer  19 53/79 days or 19.671 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Steven = 37 days

And, the number of days to finish the same work by Jonathan = 42 days

Thus, the number of days to finish the work by Steven and Jonathan together = ?

Here,

∵ In 37 days the work done by Steven = 1

∴ In 1 day, the work done by Steven = 1/37 part

Similarly,

∵ In 42 days the work done by Jonathan = 1

∴ In 1 day, the work done by Jonathan = 1/42 part

Now, in 1 day, the work done by Steven and Jonathan together

= In 1 day work done by Steven + In 1 day the work done by Jonathan

= 1/37 + 1/42

= 42 + 37/1554

= 79/1554 part of work

This means in 1 day, 79/1554 part of work is done by Steven and Jonathan working together.

Now, the number of days required to finish 79/1554 part of work by Steven + Jonathan working together = 1

∴ the number of days required to finish 1 work by Steven + Jonathan together

= 1/79/1554

= 1 × 1554/79 = 1554/79 days

= 19 53/79 days = or 19.671 days

Thus, Steven and Jonathan working together will finish the work in 19 53/79 days = or 19.671 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 Steven = 37 days

And the number of days required to finish the same work by Jonathan = 42 days

Thus, the number of days required to finish the work Steven and Jonathan working together = ?

Here a = 37 days

And, b = 42 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Steven and Jonathan working together

= 37 × 42/37 + 42 days

= 1554/79 days

= 19 53/79 days or 19.671

Thus, Steven and Jonathan together will finish the work in 19 53/79 days or 19.671 days Answer


Similar Questions

(1) If Anthony can finish the work in 28 days and Jeffrey can finish the same work in 31 days, then in how many days both can finish the work together?

(2) Amanda can finish a work in 48 days. Melissa can finish the same work in 53 days while Deborah can finish the work in 58 days. How long will it take to finish it if they work together?

(3) 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?

(4) Joshua can finish a work in 39 days. Kenneth can finish the same work in 40 days while Kevin can finish the work in 41 days. How long will it take to finish it if they work together?

(5) If Elizabeth can finish the work in 33 days and Daniel can finish the same work in 49 days, then in how many days both can finish the work together?

(6) Timothy can finish a work in 49 days. Ronald can finish the same work in 50 days while Edward can finish the work in 51 days. How long will it take to finish it if they work together?

(7) If Charles can finish the work in 20 days and Kenneth can finish the same work in 23 days, then in how many days both can finish the work together?

(8) If Debra can finish the work in 92 days and Elijah can finish the same work in 97 days, then in how many days both can finish the work together?

(9) Sarah can finish a work in 18 days. Karen can finish the same work in 19 days while Lisa can finish the work in 20 days. How long will it take to finish it if they work together?

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