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) If Carol can finish the work in 43 days and Alexander can finish the same work in 47 days, then in how many days both can finish the work together?

(2) 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?

(3) 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?

(4) 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?

(5) Anthony can finish a work in 27 days. Mark can finish the same work in 28 days while Donald can finish the work in 29 days. How long will it take to finish it if they work together?

(6) Emily can finish a work in 40 days. Michelle can finish the same work in 45 days while Carol can finish the work in 50 days. How long will it take to finish it if they work together?

(7) If Karen can finish the work in 21 days and Kevin can finish the same work in 24 days, then in how many days both can finish the work together?

(8) Mark can finish a work in 29 days. Donald can finish the same work in 30 days while Steven can finish the work in 31 days. How long will it take to finish it if they work together?

(9) If Margaret can finish the work in 29 days and Ryan can finish the same work in 33 days, then in how many days both can finish the work together?

(10) If Kevin can finish the work in 44 days and Frank can finish the same work in 48 days, then in how many days both can finish the work together?


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