Question:
Joseph can finish a work in 19 days. Charles can finish the same work in 24 days while Christopher can finish the work in 29 days. How long will it take to finish it if they work together?
Correct Answer
7 1303/1703 days or 7.765 days
Solution And Explanation
Solution
Given,
The number of days required to finish a piece of work by Joseph = 19 days
And, the number of days required to finish the same work by Charles = 24 days
And, the number of days required to finish the same work by Christopher = 29 days
Thus, the number of days required to finish the work by all of them if they work together = ?
Here,
∵ In 19 days the work is done by Joseph = 1
∴ The work done by Joseph in 1 day = 1/19
Similarly,
∵ In 24 days the work is done by Charles = 1
∴ The work done by Charles in 1 day = 1/24
Similarly,
∵ In 29 days the work is done by Christopher = 1
∴ The work done by Christopher in 1 day = 1/29 part
Now, the work done by Joseph, Charles, and Christopher together in 1 day
= Joseph's 1 day work + Charles's 1 day work + Christopher's 1 day work
= 1/19 + 1/24 + 1/29
= 696 + 551 + 456/13224
= 1703/13224 part of work
This means in 1 day, 1703/13224 part of work is done by Joseph, Charles and Christopher working together.
Now, the number of days required to finish 1703/13224 part of work by Joseph, Charles, and Christopher working together = 1
∴ the number of days required to finish the whole work (1 work) by Joseph + Charles + Christopher together
= 1/1703/13224
= 1 × 13224/1703 = 13224/1703 days
= 7 1303/1703 days = or 7.765 days
Thus, Joseph, Charles, and Christopher working together will finish the total work (1 work) in 7 1303/1703 days = or 7.765 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 Joseph = 19 days
And the number of days required to finish the same work by Charles = 24 days
And the number of days required to finish the work by Christopher = 29 days
Thus, the number of days required to finish the work by Joseph, Charles, and Christopher together = ?
Here a = 19 days
And, b = 24 days
And, c = 29 days
Thus, using formula a × b × c/ab + ac + bc days
The number of days required to finish the work when Joseph, Charles, and Christopher working together
= 19 × 24 × 29/19 × 24 + 19 × 29 + 24 × 29 days
= 13224/456 + 551 + 696 days
= 13224/1703 days
= 13224/1703 days
= 7 1303/1703 days or 7.765
Thus, Joseph, Charles, and Christopher together will finish the work in 7 1303/1703 days or 7.765 days Answer
Similar Questions
(1) Amanda can finish a work in 44 days. Dorothy can finish the same work in 45 days while Melissa can finish the work in 46 days. How long will it take to finish it if they work together?
(2) Mary can finish a work in 6 days. Jennifer can finish the same work in 11 days while Linda can finish the work in 16 days. How long will it take to finish it if they work together?
(3) If Stephanie can finish the work in 56 days and Adam can finish the same work in 61 days, then in how many days both can finish the work together?
(4) If Patricia can finish the work in 5 days and William can finish the same work in 9 days, then in how many days both can finish the work together?
(5) 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?
(6) 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?
(7) If Charles can finish the work in 20 days and Kenneth can finish the same work in 23 days, then in how many days both can finish the work together?
(8) Deborah can finish a work in 50 days. Stephanie can finish the same work in 51 days while Rebecca can finish the work in 52 days. How long will it take to finish it if they work together?
(9) If Frank can finish the work in 93 days and Randy can finish the same work in 98 days, then in how many days both can finish the work together?
(10) Carol can finish a work in 42 days. Amanda can finish the same work in 43 days while Dorothy can finish the work in 44 days. How long will it take to finish it if they work together?