Time and Work
MCQs Math


Question:     If Anna can finish the work in 74 days and Austin can finish the same work in 79 days, then in how many days both can finish the work together?


Correct Answer  38 32/153 days or 38.209 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Anna = 74 days

And, the number of days to finish the same work by Austin = 79 days

Thus, the number of days to finish the work by Anna and Austin together = ?

Here,

∵ In 74 days the work done by Anna = 1

∴ In 1 day, the work done by Anna = 1/74 part

Similarly,

∵ In 79 days the work done by Austin = 1

∴ In 1 day, the work done by Austin = 1/79 part

Now, in 1 day, the work done by Anna and Austin together

= In 1 day work done by Anna + In 1 day the work done by Austin

= 1/74 + 1/79

= 79 + 74/5846

= 153/5846 part of work

This means in 1 day, 153/5846 part of work is done by Anna and Austin working together.

Now, the number of days required to finish 153/5846 part of work by Anna + Austin working together = 1

∴ the number of days required to finish 1 work by Anna + Austin together

= 1/153/5846

= 1 × 5846/153 = 5846/153 days

= 38 32/153 days = or 38.209 days

Thus, Anna and Austin working together will finish the work in 38 32/153 days = or 38.209 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 Anna = 74 days

And the number of days required to finish the same work by Austin = 79 days

Thus, the number of days required to finish the work Anna and Austin working together = ?

Here a = 74 days

And, b = 79 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Anna and Austin working together

= 74 × 79/74 + 79 days

= 5846/153 days

= 38 32/153 days or 38.209

Thus, Anna and Austin together will finish the work in 38 32/153 days or 38.209 days Answer


Similar Questions

(1) If Betty can finish the work in 30 days and Jason can finish the same work in 35 days, then in how many days both can finish the work together?

(2) George can finish a work in 47 days. Timothy can finish the same work in 48 days while Ronald can finish the work in 49 days. How long will it take to finish it if they work together?

(3) If Jennifer can finish the work in 7 days and Joseph can finish the same work in 10 days, then in how many days both can finish the work together?

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(6) If Kenneth can finish the work in 42 days and Gregory can finish the same work in 46 days, then in how many days both can finish the work together?

(7) If Dorothy can finish the work in 50 days and Jack can finish the same work in 55 days, then in how many days both can finish the work together?

(8) If Matthew can finish the work in 26 days and Edward can finish the same work in 29 days, then in how many days both can finish the work together?

(9) Paul can finish a work in 35 days. Andrew can finish the same work in 36 days while Joshua can finish the work in 37 days. How long will it take to finish it if they work together?

(10) If John can finish the work in 9 days and Richard can finish the same work in 14 days, then in how many days both can finish the work together?


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