Time and Work
MCQs Math


Question:     If Eric can finish the work in 71 days and Gerald can finish the same work in 76 days, then in how many days both can finish the work together?


Correct Answer  36 104/147 days or 36.707 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Eric = 71 days

And, the number of days to finish the same work by Gerald = 76 days

Thus, the number of days to finish the work by Eric and Gerald together = ?

Here,

∵ In 71 days the work done by Eric = 1

∴ In 1 day, the work done by Eric = 1/71 part

Similarly,

∵ In 76 days the work done by Gerald = 1

∴ In 1 day, the work done by Gerald = 1/76 part

Now, in 1 day, the work done by Eric and Gerald together

= In 1 day work done by Eric + In 1 day the work done by Gerald

= 1/71 + 1/76

= 76 + 71/5396

= 147/5396 part of work

This means in 1 day, 147/5396 part of work is done by Eric and Gerald working together.

Now, the number of days required to finish 147/5396 part of work by Eric + Gerald working together = 1

∴ the number of days required to finish 1 work by Eric + Gerald together

= 1/147/5396

= 1 × 5396/147 = 5396/147 days

= 36 104/147 days = or 36.707 days

Thus, Eric and Gerald working together will finish the work in 36 104/147 days = or 36.707 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 Eric = 71 days

And the number of days required to finish the same work by Gerald = 76 days

Thus, the number of days required to finish the work Eric and Gerald working together = ?

Here a = 71 days

And, b = 76 days

Thus, using formula a × b/a + b days

The number of days required to finish the work when Eric and Gerald working together

= 71 × 76/71 + 76 days

= 5396/147 days

= 36 104/147 days or 36.707

Thus, Eric and Gerald together will finish the work in 36 104/147 days or 36.707 days Answer


Similar Questions

(1) If Mary can finish the work in 25 days and Michael can finish the same work in 41 days, then in how many days both can finish the work together?

(2) Eric can finish a work in 71 days. Stephen can finish the same work in 76 days while Larry can finish the work in 81 days. How long will it take to finish it if they work together?

(3) If Steven can finish the work in 37 days and Jonathan can finish the same work in 42 days, then in how many days both can finish the work together?

(4) If Nicholas can finish the work in 69 days and Roger can finish the same work in 74 days, then in how many days both can finish the work together?

(5) Barbara can finish a work in 16 days. Jessica can finish the same work in 21 days while Sarah can finish the work in 26 days. How long will it take to finish it if they work together?

(6) If Robert can finish the work in 26 days and David can finish the same work in 42 days, then in how many days both can finish the work together?

(7) Jessica can finish a work in 20 days. Karen can finish the same work in 25 days while Lisa can finish the work in 30 days. How long will it take to finish it if they work together?

(8) If Joseph can finish the work in 16 days and Steven can finish the same work in 20 days, then in how many days both can finish the work together?

(9) If Patrick can finish the work in 95 days and Vincent can finish the same work in 100 days, then in how many days both can finish the work together?

(10) Pamela can finish a work in 78 days. Nicole can finish the same work in 83 days while Helen can finish the work in 88 days. How long will it take to finish it if they work together?


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