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

(1) George can finish a work in 51 days. Ronald can finish the same work in 56 days while Edward can finish the work in 61 days. How long will it take to finish it if they work together?

(2) If Alexander can finish the work in 91 days and Wayne can finish the same work in 96 days, then in how many days both can finish the work together?

(3) Patrick can finish a work in 95 days. Jack can finish the same work in 100 days while Dennis can finish the work in 105 days. How long will it take to finish it if they work together?

(4) Charles can finish a work in 23 days. Daniel can finish the same work in 28 days while Matthew can finish the work in 33 days. How long will it take to finish it if they work together?

(5) If Ronald can finish the work in 55 days and Jose can finish the same work in 60 days, then in how many days both can finish the work together?

(6) If Donald can finish the work in 32 days and Nicholas can finish the same work in 35 days, then in how many days both can finish the work together?

(7) If William can finish the work in 12 days and Matthew can finish the same work in 16 days, then in how many days both can finish the work together?

(8) Jennifer can finish a work in 10 days. Elizabeth can finish the same work in 15 days while Barbara can finish the work in 20 days. How long will it take to finish it if they work together?

(9) If Kenneth can finish the work in 42 days and Gregory can finish the same work in 46 days, then in how many days both can finish the work together?

(10) Michelle can finish a work in 44 days. Amanda can finish the same work in 49 days while Dorothy can finish the work in 54 days. How long will it take to finish it if they work together?


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