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 Angela can finish the work in 70 days and Terry can finish the same work in 75 days, then in how many days both can finish the work together?

(2) If Stephanie can finish the work in 56 days and Adam can finish the same work in 61 days, then in how many days both can finish the work together?

(3) 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?

(4) If Pamela can finish the work in 78 days and Dylan can finish the same work in 83 days, then in how many days both can finish the work together?

(5) 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?

(6) If Kenneth can finish the work in 42 days and Gregory can finish the same work in 45 days, then in how many days both can finish the work together?

(7) If Jacob can finish the work in 65 days and Noah can finish the same work in 70 days, then in how many days both can finish the work together?

(8) Sharon can finish a work in 60 days. Cynthia can finish the same work in 65 days while Kathleen can finish the work in 70 days. How long will it take to finish it if they work together?

(9) Cynthia can finish a work in 64 days. Amy can finish the same work in 69 days while Angela can finish the work in 74 days. How long will it take to finish it if they work together?

(10) 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?


NCERT Solution and CBSE Notes for class twelve, eleventh, tenth, ninth, seventh, sixth, fifth, fourth and General Math for competitive Exams. ©