Time and Work
MCQs Math


Question:     If Emily can finish the work in 37 days and Justin can finish the same work in 41 days, then in how many days both can finish the work together?


Correct Answer  19 35/78 days or 19.449 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Emily = 37 days

And, the number of days to finish the same work by Justin = 41 days

Thus, the number of days to finish the work by Emily and Justin together = ?

Here,

∵ In 37 days the work done by Emily = 1

∴ In 1 day, the work done by Emily = 1/37 part

Similarly,

∵ In 41 days the work done by Justin = 1

∴ In 1 day, the work done by Justin = 1/41 part

Now, in 1 day, the work done by Emily and Justin together

= In 1 day work done by Emily + In 1 day the work done by Justin

= 1/37 + 1/41

= 41 + 37/1517

= 78/1517 part of work

This means in 1 day, 78/1517 part of work is done by Emily and Justin working together.

Now, the number of days required to finish 78/1517 part of work by Emily + Justin working together = 1

∴ the number of days required to finish 1 work by Emily + Justin together

= 1/78/1517

= 1 × 1517/78 = 1517/78 days

= 19 35/78 days = or 19.449 days

Thus, Emily and Justin working together will finish the work in 19 35/78 days = or 19.449 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 Emily = 37 days

And the number of days required to finish the same work by Justin = 41 days

Thus, the number of days required to finish the work Emily and Justin working together = ?

Here a = 37 days

And, b = 41 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Emily and Justin working together

= 37 × 41/37 + 41 days

= 1517/78 days

= 19 35/78 days or 19.449

Thus, Emily and Justin together will finish the work in 19 35/78 days or 19.449 days Answer


Similar Questions

(1) If Susan can finish the work in 15 days and Donald can finish the same work in 19 days, then in how many days both can finish the work together?

(2) Ashley can finish a work in 32 days. Kimberly can finish the same work in 33 days while Emily can finish the work in 34 days. How long will it take to finish it if they work together?

(3) If George can finish the work in 48 days and Dennis can finish the same work in 51 days, then in how many days both can finish the work together?

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(5) 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?

(6) Deborah can finish a work in 54 days. Rebecca can finish the same work in 59 days while Sharon can finish the work in 64 days. How long will it take to finish it if they work together?

(7) Robert can finish a work in 3 days. John can finish the same work in 4 days while Michael can finish the work in 5 days. How long will it take to finish it if they work together?

(8) Brandon can finish a work in 83 days. Samuel can finish the same work in 88 days while Gregory can finish the work in 93 days. How long will it take to finish it if they work together?

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