Time and Work
MCQs Math


Question:     If Annie can finish a work in 2 days and Bobby can finish the same work in 3 days, then in how many days they both can finish the work working together?


Correct Answer  6/5 days or 11/5 days or 1.2 days

Solution And Explanation

Solution

Given,

The number of days to finish the work by Annie = 2 days

And, the number of days to finish the same work by Bobby = 3 days

Thus, the number of days to finish the work by Annie and Bobby working together = ?

Here, ∵ In 2 days the work done by Annie = 1

∴ In 1 day, the work done by Annie = 1/2 part

Similarly, ∵ In 3 days the work done by Bobby = 1

∴ In 1 day, the work done by Bobby = 1/3 part

Now, in 1 day, the work done by Annie and Bobby working together

= In 1 day work done by Annie + In 1 day the work done by Bobby

= 1/2 + 1/3

= 3 + 2/6

= 5/6

This means in 1 day, 5/6 part of work is done by Annie and Bobby working together.

Now, the number of days required to finish 5/6 part work by Annie + Bobby working together = 1

∴ the number of days required to finish 1 work by Robert + Bob working together

= 1/5/6

= 1 × 6/5 days = 6/5 days

= 6/5 or 1 1/5 days or 1.2 days

Thus, Annie and Bobby working together will finish the work in 6/5 or 1 1/5 days or 1.2 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 to finish the work by Annie = 2 days

And, the number of days to finish the same work by Bobby = 3 days

Thus, the number of days to finish the work by Annie and Bobby working together = ?

Here "a" = 2 days

And, "b" = 3 days

Thus, using formula a × b/a + b days

The number of days require to finish the work when Annie and Bobby working together

= 2 × 3/2 + 3

= 6/5 days or 11/5 days or 1.2 days

Thus, Annie and Bobby working together will finish the work in 6/5 days or 11/5 days or 1.2 days Answer


Similar Questions

(1) If Thomas can finish the work in 18 days and Andrew can finish the same work in 22 days, then in how many days both can finish the work together?

(2) If Sarah can finish the work in 19 days and Joshua can finish the same work in 22 days, then in how many days both can finish the work together?

(3) Ashley can finish a work in 36 days. Emily can finish the same work in 41 days while Donna can finish the work in 46 days. How long will it take to finish it if they work together?

(4) Dorothy can finish a work in 46 days. Melissa can finish the same work in 47 days while Deborah can finish the work in 48 days. How long will it take to finish it if they work together?

(5) 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?

(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 Margaret can finish the work in 32 days and Ryan can finish the same work in 37 days, then in how many days both can finish the work together?

(8) 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?

(9) If Lisa can finish the work in 23 days and George can finish the same work in 26 days, then in how many days both can finish the work together?

(10) 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?


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