Time and Work
MCQs Math


Question:     If Michael can finish the work in 30 days and Thomas can finish the same work in 46 days, then in how many days both can finish the work together?


Correct Answer  18 3/19 days or 18.158 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Michael = 30 days

And, the number of days to finish the same work by Thomas = 46 days

Thus, the number of days to finish the work by Michael and Thomas together = ?

Here,

∵ In 30 days the work done by Michael = 1

∴ In 1 day, the work done by Michael = 1/30 part

Similarly,

∵ In 46 days the work done by Thomas = 1

∴ In 1 day, the work done by Thomas = 1/46 part

Now, in 1 day, the work done by Michael and Thomas together

= In 1 day work done by Michael + In 1 day the work done by Thomas

= 1/30 + 1/46

= 23 + 15/690

= 38/690 part of work

= 38 ÷ 2/690 ÷ 2 part of work

= 19/345 part of work

This means, in 1 day, 19/345 part of the work is done by Michael and Thomas together.

Now, the number of days required to finish 19/345 part of work by Michael + Thomas working together = 1

∴ the number of days required to finish 1 work by Michael + Thomas together

= 1/19/345

= 1 × 345/19 = 345/19 days

= 18 3/19 days = or 18.158 days

Thus, Michael and Thomas working together will finish the work in 18 3/19 days = or 18.158 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 Michael = 30 days

And the number of days required to finish the same work by Thomas = 46 days

Thus, the number of days required to finish the work Michael and Thomas working together = ?

Here a = 30 days

And, b = 46 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Michael and Thomas working together

= 30 × 46/30 + 46 days

= 1380/76 days

= 1380 ÷ 4/76 ÷ 4 = 345/19 days

= 18 3/19 days or 18.158

Thus, Michael and Thomas together will finish the work in 18 3/19 days or 18.158 days Answer


Similar Questions

(1) 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?

(2) If Daniel can finish the work in 24 days and Timothy can finish the same work in 27 days, then in how many days both can finish the work together?

(3) Patrick can finish a work in 95 days. Jack can finish the same work in 100 days while Dennis can finish the work in 105 days. How long will it take to finish it if they work together?

(4) If Cynthia can finish the work in 64 days and Walter can finish the same work in 69 days, then in how many days both can finish the work together?

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(6) Michelle can finish a work in 44 days. Amanda can finish the same work in 49 days while Dorothy can finish the work in 54 days. How long will it take to finish it if they work together?

(7) Linda can finish a work in 8 days. Elizabeth can finish the same work in 9 days while Barbara can finish the work in 10 days. How long will it take to finish it if they work together?

(8) If Gary can finish the work in 67 days and Christian can finish the same work in 72 days, then in how many days both can finish the work together?

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(10) If Donald can finish the work in 32 days and Nicholas can finish the same work in 36 days, then in how many days both can finish the work together?


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