Time and Work
MCQs Math


Question:     If Deborah can finish the work in 54 days and Aaron can finish the same work in 59 days, then in how many days both can finish the work together?


Correct Answer  28 22/113 days or 28.195 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Deborah = 54 days

And, the number of days to finish the same work by Aaron = 59 days

Thus, the number of days to finish the work by Deborah and Aaron together = ?

Here,

∵ In 54 days the work done by Deborah = 1

∴ In 1 day, the work done by Deborah = 1/54 part

Similarly,

∵ In 59 days the work done by Aaron = 1

∴ In 1 day, the work done by Aaron = 1/59 part

Now, in 1 day, the work done by Deborah and Aaron together

= In 1 day work done by Deborah + In 1 day the work done by Aaron

= 1/54 + 1/59

= 59 + 54/3186

= 113/3186 part of work

This means in 1 day, 113/3186 part of work is done by Deborah and Aaron working together.

Now, the number of days required to finish 113/3186 part of work by Deborah + Aaron working together = 1

∴ the number of days required to finish 1 work by Deborah + Aaron together

= 1/113/3186

= 1 × 3186/113 = 3186/113 days

= 28 22/113 days = or 28.195 days

Thus, Deborah and Aaron working together will finish the work in 28 22/113 days = or 28.195 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 Deborah = 54 days

And the number of days required to finish the same work by Aaron = 59 days

Thus, the number of days required to finish the work Deborah and Aaron working together = ?

Here a = 54 days

And, b = 59 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Deborah and Aaron working together

= 54 × 59/54 + 59 days

= 3186/113 days

= 28 22/113 days or 28.195

Thus, Deborah and Aaron together will finish the work in 28 22/113 days or 28.195 days Answer


Similar Questions

(1) Frank can finish a work in 93 days. Raymond can finish the same work in 98 days while Jack can finish the work in 103 days. How long will it take to finish it if they work together?

(2) If Stephen can finish the work in 75 days and Carl can finish the same work in 80 days, then in how many days both can finish the work together?

(3) Anna can finish a work in 74 days. Pamela can finish the same work in 79 days while Emma can finish the work in 84 days. How long will it take to finish it if they work together?

(4) If Carol can finish the work in 43 days and Alexander can finish the same work in 46 days, then in how many days both can finish the work together?

(5) Carol can finish a work in 46 days. Dorothy can finish the same work in 51 days while Melissa can finish the work in 56 days. How long will it take to finish it if they work together?

(6) William can finish a work in 15 days. Joseph can finish the same work in 20 days while Thomas can finish the work in 25 days. How long will it take to finish it if they work together?

(7) If Patrick can finish the work in 95 days and Vincent can finish the same work in 100 days, then in how many days both can finish the work together?

(8) If Jack can finish the work in 99 days and Bobby can finish the same work in 104 days, then in how many days both can finish the work together?

(9) Robert can finish a work in 7 days. Michael can finish the same work in 12 days while David can finish the work in 17 days. How long will it take to finish it if they work together?

(10) Thomas can finish a work in 21 days. Christopher can finish the same work in 26 days while Daniel can finish the work in 31 days. How long will it take to finish it if they work together?


NCERT Solution and CBSE Notes for class twelve, eleventh, tenth, ninth, seventh, sixth, fifth, fourth and General Math for competitive Exams. ©