Time and Work
MCQs Math


Question:     Edward can finish a work in 57 days. Jeffrey can finish the same work in 62 days while Ryan can finish the work in 67 days. How long will it take to finish it if they work together?


Correct Answer  20 6638/11507 days or 20.577 days

Solution And Explanation

Solution

Given,

The number of days required to finish a piece of work by Edward = 57 days

And, the number of days required to finish the same work by Jeffrey = 62 days

And, the number of days required to finish the same work by Ryan = 67 days

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

Here,

∵ In 57 days the work is done by Edward = 1

∴ The work done by Edward in 1 day = 1/57

Similarly,

∵ In 62 days the work is done by Jeffrey = 1

∴ The work done by Jeffrey in 1 day = 1/62

Similarly,

∵ In 67 days the work is done by Ryan = 1

∴ The work done by Ryan in 1 day = 1/67 part

Now, the work done by Edward, Jeffrey, and Ryan together in 1 day

= Edward's 1 day work + Jeffrey's 1 day work + Ryan's 1 day work

= 1/57 + 1/62 + 1/67

= 4154 + 3819 + 3534/236778

= 11507/236778 part of work

This means in 1 day, 11507/236778 part of work is done by Edward, Jeffrey and Ryan working together.

Now, the number of days required to finish 11507/236778 part of work by Edward, Jeffrey, and Ryan working together = 1

∴ the number of days required to finish the whole work (1 work) by Edward + Jeffrey + Ryan together

= 1/11507/236778

= 1 × 236778/11507 = 236778/11507 days

= 20 6638/11507 days = or 20.577 days

Thus, Edward, Jeffrey, and Ryan working together will finish the total work (1 work) in 20 6638/11507 days = or 20.577 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 Edward = 57 days

And the number of days required to finish the same work by Jeffrey = 62 days

And the number of days required to finish the work by Ryan = 67 days

Thus, the number of days required to finish the work by Edward, Jeffrey, and Ryan together = ?

Here a = 57 days

And, b = 62 days

And, c = 67 days

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

The number of days required to finish the work when Edward, Jeffrey, and Ryan working together

= 57 × 62 × 67/57 × 62 + 57 × 67 + 62 × 67 days

= 236778/3534 + 3819 + 4154 days

= 236778/11507 days

= 236778/11507 days

= 20 6638/11507 days or 20.577

Thus, Edward, Jeffrey, and Ryan together will finish the work in 20 6638/11507 days or 20.577 days Answer


Similar Questions

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(2) Catherine can finish a work in 100 days. Heather can finish the same work in 105 days while Diane can finish the work in 110 days. How long will it take to finish it if they work together?

(3) 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?

(4) If Daniel can finish the work in 27 days and Timothy can finish the same work in 32 days, then in how many days both can finish the work together?

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(6) If Karen can finish the work in 21 days and Kevin can finish the same work in 25 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 15 days, then in how many days both can finish the work together?

(8) Stephanie can finish a work in 56 days. Sharon can finish the same work in 61 days while Laura can finish the work in 66 days. How long will it take to finish it if they work together?

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