Time and Work
MCQs Math


Question:     Brian can finish a work in 49 days. Timothy can finish the same work in 54 days while Ronald can finish the work in 59 days. How long will it take to finish it if they work together?


Correct Answer  17 7823/8723 days or 17.897 days

Solution And Explanation

Solution

Given,

The number of days required to finish a piece of work by Brian = 49 days

And, the number of days required to finish the same work by Timothy = 54 days

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

Thus, the number of days required to finish the work by all of them if they work together = ?

Here,

∵ In 49 days the work is done by Brian = 1

∴ The work done by Brian in 1 day = 1/49

Similarly,

∵ In 54 days the work is done by Timothy = 1

∴ The work done by Timothy in 1 day = 1/54

Similarly,

∵ In 59 days the work is done by Ronald = 1

∴ The work done by Ronald in 1 day = 1/59 part

Now, the work done by Brian, Timothy, and Ronald together in 1 day

= Brian's 1 day work + Timothy's 1 day work + Ronald's 1 day work

= 1/49 + 1/54 + 1/59

= 3186 + 2891 + 2646/156114

= 8723/156114 part of work

This means in 1 day, 8723/156114 part of work is done by Brian, Timothy and Ronald working together.

Now, the number of days required to finish 8723/156114 part of work by Brian, Timothy, and Ronald working together = 1

∴ the number of days required to finish the whole work (1 work) by Brian + Timothy + Ronald together

= 1/8723/156114

= 1 × 156114/8723 = 156114/8723 days

= 17 7823/8723 days = or 17.897 days

Thus, Brian, Timothy, and Ronald working together will finish the total work (1 work) in 17 7823/8723 days = or 17.897 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, B can finish the same work in b days, and C can finish the work in c days
then working together the number of days required to finish the work
= a × b × c/ab + ac + bc days.

Here given,

The number of days required to finish the work by Brian = 49 days

And the number of days required to finish the same work by Timothy = 54 days

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

Thus, the number of days required to finish the work by Brian, Timothy, and Ronald together = ?

Here a = 49 days

And, b = 54 days

And, c = 59 days

Thus, using formula a × b × c/ab + ac + bc days

The number of days required to finish the work when Brian, Timothy, and Ronald working together

= 49 × 54 × 59/49 × 54 + 49 × 59 + 54 × 59 days

= 156114/2646 + 2891 + 3186 days

= 156114/8723 days

= 156114/8723 days

= 17 7823/8723 days or 17.897

Thus, Brian, Timothy, and Ronald together will finish the work in 17 7823/8723 days or 17.897 days Answer


Similar Questions

(1) If Richard can finish the work in 17 days and Mark can finish the same work in 22 days, then in how many days both can finish the work together?

(2) If David can finish the work in 32 days and Christopher can finish the same work in 48 days, then in how many days both can finish the work together?

(3) Jessica can finish a work in 16 days. Sarah can finish the same work in 17 days while Karen can finish the work in 18 days. How long will it take to finish it if they work together?

(4) 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?

(5) Charles can finish a work in 19 days. Christopher can finish the same work in 20 days while Daniel can finish the work in 21 days. How long will it take to finish it if they work together?

(6) Brandon can finish a work in 83 days. Samuel can finish the same work in 88 days while Gregory can finish the work in 93 days. How long will it take to finish it if they work together?

(7) 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?

(8) Mark can finish a work in 29 days. Donald can finish the same work in 30 days while Steven can finish the work in 31 days. How long will it take to finish it if they work together?

(9) Paul can finish a work in 35 days. Andrew can finish the same work in 36 days while Joshua can finish the work in 37 days. How long will it take to finish it if they work together?

(10) If Paul can finish the work in 39 days and Larry can finish the same work in 44 days, then in how many days both can finish the work together?


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