Time and Work
MCQs Math


Question:     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?


Correct Answer  3 1/13 days or 3.077 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Patricia = 5 days

And, the number of days to finish the same work by William = 8 days

Thus, the number of days to finish the work by Patricia and William together = ?

Here,

∵ In 5 days the work done by Patricia = 1

∴ In 1 day, the work done by Patricia = 1/5 part

Similarly,

∵ In 8 days the work done by William = 1

∴ In 1 day, the work done by William = 1/8 part

Now, in 1 day, the work done by Patricia and William together

= In 1 day work done by Patricia + In 1 day the work done by William

= 1/5 + 1/8

= 8 + 5/40

= 13/40 part of work

This means in 1 day, 13/40 part of work is done by Patricia and William working together.

Now, the number of days required to finish 13/40 part of work by Patricia + William working together = 1

∴ the number of days required to finish 1 work by Patricia + William together

= 1/13/40

= 1 × 40/13 = 40/13 days

= 3 1/13 days = or 3.077 days

Thus, Patricia and William working together will finish the work in 3 1/13 days = or 3.077 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, and B can finish the same work in b days,
then working together the number of days require to finish the work
= a × b/a + b days.

Here given,

The number of days required to finish the work by Patricia = 5 days

And the number of days required to finish the same work by William = 8 days

Thus, the number of days required to finish the work Patricia and William working together = ?

Here a = 5 days

And, b = 8 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Patricia and William working together

= 5 × 8/5 + 8 days

= 40/13 days

= 3 1/13 days or 3.077

Thus, Patricia and William together will finish the work in 3 1/13 days or 3.077 days Answer


Similar Questions

(1) If Kenneth can finish the work in 45 days and Gregory can finish the same work in 50 days, then in how many days both can finish the work together?

(2) If Emily can finish the work in 40 days and Justin can finish the same work in 45 days, then in how many days both can finish the work together?

(3) If Barbara can finish the work in 13 days and Anthony can finish the same work in 17 days, then in how many days both can finish the work together?

(4) 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?

(5) If Christopher can finish the work in 25 days and Brian can finish the same work in 30 days, then in how many days both can finish the work together?

(6) 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?

(7) 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?

(8) If Kimberly can finish the work in 35 days and Stephen can finish the same work in 38 days, then in how many days both can finish the work together?

(9) Jack can finish a work in 99 days. Jerry can finish the same work in 104 days while Tyler can finish the work in 109 days. How long will it take to finish it if they work together?

(10) If Patricia can finish the work in 8 days and William can finish the same work in 13 days, then in how many days both can finish the work together?


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