Time and Work
MCQs Math


Question:     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?


Correct Answer  26 2458/9349 days or 26.263 days

Solution And Explanation

Solution

Given,

The number of days required to finish a piece of work by Anna = 74 days

And, the number of days required to finish the same work by Pamela = 79 days

And, the number of days required to finish the same work by Emma = 84 days

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

Here,

∵ In 74 days the work is done by Anna = 1

∴ The work done by Anna in 1 day = 1/74

Similarly,

∵ In 79 days the work is done by Pamela = 1

∴ The work done by Pamela in 1 day = 1/79

Similarly,

∵ In 84 days the work is done by Emma = 1

∴ The work done by Emma in 1 day = 1/84 part

Now, the work done by Anna, Pamela, and Emma together in 1 day

= Anna's 1 day work + Pamela's 1 day work + Emma's 1 day work

= 1/74 + 1/79 + 1/84

= 3318 + 3108 + 2923/245532

= 9349/245532 part of work

This means in 1 day, 9349/245532 part of work is done by Anna, Pamela and Emma working together.

Now, the number of days required to finish 9349/245532 part of work by Anna, Pamela, and Emma working together = 1

∴ the number of days required to finish the whole work (1 work) by Anna + Pamela + Emma together

= 1/9349/245532

= 1 × 245532/9349 = 245532/9349 days

= 26 2458/9349 days = or 26.263 days

Thus, Anna, Pamela, and Emma working together will finish the total work (1 work) in 26 2458/9349 days = or 26.263 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 Anna = 74 days

And the number of days required to finish the same work by Pamela = 79 days

And the number of days required to finish the work by Emma = 84 days

Thus, the number of days required to finish the work by Anna, Pamela, and Emma together = ?

Here a = 74 days

And, b = 79 days

And, c = 84 days

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

The number of days required to finish the work when Anna, Pamela, and Emma working together

= 74 × 79 × 84/74 × 79 + 74 × 84 + 79 × 84 days

= 491064/5846 + 6216 + 6636 days

= 491064/18698 days

= 491064/18698 days

= 491064 ÷ 2/18698 ÷ 2 = 245532/9349 days

= 26 2458/9349 days or 26.263

Thus, Anna, Pamela, and Emma together will finish the work in 26 2458/9349 days or 26.263 days Answer


Similar Questions

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(2) If William can finish the work in 34 days and Matthew can finish the same work in 50 days, then in how many days both can finish the work together?

(3) If Donna can finish the work in 42 days and Brandon can finish the same work in 47 days, then in how many days both can finish the work together?

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(5) If Annie can finish a work in 6 days and Bobby can finish the same work in 12 days, then in how many days they both can finish the work working together?

(6) Rebecca can finish a work in 58 days. Laura can finish the same work in 63 days while Cynthia can finish the work in 68 days. How long will it take to finish it if they work together?

(7) If Elizabeth can finish the work in 11 days and Daniel can finish the same work in 15 days, then in how many days both can finish the work together?

(8) 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?

(9) If Linda can finish the work in 31 days and Charles can finish the same work in 47 days, then in how many days both can finish the work together?

(10) If Richard can finish the work in 14 days and Mark can finish the same work in 17 days, then in how many days both can finish the work together?


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