Time and Work
MCQs Math


Question:     If Patricia can finish the work in 27 days and William can finish the same work in 43 days, then in how many days both can finish the work together?


Correct Answer  16 41/70 days or 16.586 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Patricia = 27 days

And, the number of days to finish the same work by William = 43 days

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

Here,

∵ In 27 days the work done by Patricia = 1

∴ In 1 day, the work done by Patricia = 1/27 part

Similarly,

∵ In 43 days the work done by William = 1

∴ In 1 day, the work done by William = 1/43 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

= 1/27 + 1/43

= 43 + 27/1161

= 70/1161 part of work

This means in 1 day, 70/1161 part of work is done by Patricia and William working together.

Now, the number of days required to finish 70/1161 part of work by Patricia + William working together = 1

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

= 1/70/1161

= 1 × 1161/70 = 1161/70 days

= 16 41/70 days = or 16.586 days

Thus, Patricia and William working together will finish the work in 16 41/70 days = or 16.586 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 = 27 days

And the number of days required to finish the same work by William = 43 days

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

Here a = 27 days

And, b = 43 days

Thus, using formula a × b/a + b days

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

= 27 × 43/27 + 43 days

= 1161/70 days

= 16 41/70 days or 16.586

Thus, Patricia and William together will finish the work in 16 41/70 days or 16.586 days Answer


Similar Questions

(1) Margaret can finish a work in 28 days. Sandra can finish the same work in 29 days while Ashley can finish the work in 30 days. How long will it take to finish it if they work together?

(2) If Amanda can finish the work in 45 days and Patrick can finish the same work in 48 days, then in how many days both can finish the work together?

(3) Donald can finish a work in 31 days. Steven can finish the same work in 32 days while Paul can finish the work in 33 days. How long will it take to finish it if they work together?

(4) If A can finish a work in 10 days and B can finish the same work in 15 days, then in how many days they both can finish the work working together?

(5) Janet can finish a work in 98 days. Maria can finish the same work in 103 days while Heather can finish the work in 108 days. How long will it take to finish it if they work together?

(6) If Shirley can finish the work in 72 days and Harold can finish the same work in 77 days, then in how many days both can finish the work together?

(7) If Catherine can finish the work in 100 days and Mason can finish the same work in 105 days, then in how many days both can finish the work together?

(8) If Samuel can finish the work in 87 days and Albert can finish the same work in 92 days, then in how many days both can finish the work together?

(9) If David can finish the work in 32 days and Christopher can finish the same work in 48 days, then in how many days both can finish the work together?

(10) Brian can finish a work in 45 days. George can finish the same work in 46 days while Timothy can finish the work in 47 days. How long will it take to finish it if they work together?


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