Time and Work
MCQs Math


Question:     If Joshua can finish the work in 43 days and Benjamin can finish the same work in 48 days, then in how many days both can finish the work together?


Correct Answer  22 62/91 days or 22.681 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Joshua = 43 days

And, the number of days to finish the same work by Benjamin = 48 days

Thus, the number of days to finish the work by Joshua and Benjamin together = ?

Here,

∵ In 43 days the work done by Joshua = 1

∴ In 1 day, the work done by Joshua = 1/43 part

Similarly,

∵ In 48 days the work done by Benjamin = 1

∴ In 1 day, the work done by Benjamin = 1/48 part

Now, in 1 day, the work done by Joshua and Benjamin together

= In 1 day work done by Joshua + In 1 day the work done by Benjamin

= 1/43 + 1/48

= 48 + 43/2064

= 91/2064 part of work

This means in 1 day, 91/2064 part of work is done by Joshua and Benjamin working together.

Now, the number of days required to finish 91/2064 part of work by Joshua + Benjamin working together = 1

∴ the number of days required to finish 1 work by Joshua + Benjamin together

= 1/91/2064

= 1 × 2064/91 = 2064/91 days

= 22 62/91 days = or 22.681 days

Thus, Joshua and Benjamin working together will finish the work in 22 62/91 days = or 22.681 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 Joshua = 43 days

And the number of days required to finish the same work by Benjamin = 48 days

Thus, the number of days required to finish the work Joshua and Benjamin working together = ?

Here a = 43 days

And, b = 48 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Joshua and Benjamin working together

= 43 × 48/43 + 48 days

= 2064/91 days

= 22 62/91 days or 22.681

Thus, Joshua and Benjamin together will finish the work in 22 62/91 days or 22.681 days Answer


Similar Questions

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(2) If Jeffrey can finish the work in 61 days and Peter can finish the same work in 66 days, then in how many days both can finish the work together?

(3) If Mark can finish the work in 33 days and Jacob can finish the same work in 38 days, then in how many days both can finish the work together?

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(6) If Emily can finish the work in 37 days and Justin can finish the same work in 40 days, then in how many days both can finish the work together?

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