Time and Work
MCQs Math


Question:     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?


Correct Answer  16 788/3589 days or 16.22 days

Solution And Explanation

Solution

Given,

The number of days required to finish a piece of work by Michelle = 44 days

And, the number of days required to finish the same work by Amanda = 49 days

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

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

Here,

∵ In 44 days the work is done by Michelle = 1

∴ The work done by Michelle in 1 day = 1/44

Similarly,

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

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

Similarly,

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

∴ The work done by Dorothy in 1 day = 1/54 part

Now, the work done by Michelle, Amanda, and Dorothy together in 1 day

= Michelle's 1 day work + Amanda's 1 day work + Dorothy's 1 day work

= 1/44 + 1/49 + 1/54

= 1323 + 1188 + 1078/58212

= 3589/58212 part of work

This means in 1 day, 3589/58212 part of work is done by Michelle, Amanda and Dorothy working together.

Now, the number of days required to finish 3589/58212 part of work by Michelle, Amanda, and Dorothy working together = 1

∴ the number of days required to finish the whole work (1 work) by Michelle + Amanda + Dorothy together

= 1/3589/58212

= 1 × 58212/3589 = 58212/3589 days

= 16 788/3589 days = or 16.22 days

Thus, Michelle, Amanda, and Dorothy working together will finish the total work (1 work) in 16 788/3589 days = or 16.22 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 Michelle = 44 days

And the number of days required to finish the same work by Amanda = 49 days

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

Thus, the number of days required to finish the work by Michelle, Amanda, and Dorothy together = ?

Here a = 44 days

And, b = 49 days

And, c = 54 days

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

The number of days required to finish the work when Michelle, Amanda, and Dorothy working together

= 44 × 49 × 54/44 × 49 + 44 × 54 + 49 × 54 days

= 116424/2156 + 2376 + 2646 days

= 116424/7178 days

= 116424/7178 days

= 116424 ÷ 2/7178 ÷ 2 = 58212/3589 days

= 16 788/3589 days or 16.22

Thus, Michelle, Amanda, and Dorothy together will finish the work in 16 788/3589 days or 16.22 days Answer


Similar Questions

(1) If Charles can finish the work in 20 days and Kenneth can finish the same work in 24 days, then in how many days both can finish the work together?

(2) If Matthew can finish the work in 26 days and Edward can finish the same work in 29 days, then in how many days both can finish the work together?

(3) If Mary can finish the work in 25 days and Michael can finish the same work in 41 days, then in how many days both can finish the work together?

(4) If Elizabeth can finish the work in 11 days and Daniel can finish the same work in 14 days, then in how many days both can finish the work together?

(5) If Donald can finish the work in 35 days and Nicholas can finish the same work in 40 days, then in how many days both can finish the work together?

(6) If Timothy can finish the work in 53 days and Tyler can finish the same work in 58 days, then in how many days both can finish the work together?

(7) Kimberly can finish a work in 34 days. Emily can finish the same work in 35 days while Donna can finish the work in 36 days. How long will it take to finish it if they work together?

(8) 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?

(9) John can finish a work in 9 days. David can finish the same work in 14 days while William can finish the work in 19 days. How long will it take to finish it if they work together?

(10) If Patricia can finish the work in 5 days and William can finish the same work in 8 days, then in how many days both can finish the work together?


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