Question

A and B working together for a certain job after working 4 hours together A left the working place for another duty and B accomplished the remaining 25% of the work in 4 hours find the time required for A to complete the whole job when working alone

Answer 1

To find the time required for A to complete the whole job when working alone, we need to understand the work done by A and B together and B alone. When A and B work together for 4 hours, they complete 100% of the work. When B works alone for 4 hours, he completes 25% of the work. A's work rate alone is 18.75% per hour. Therefore, it will take A approximately 5.33 hours to complete the whole job when working alone.

Step-by-step explanation:

To find the time required for A to complete the whole job when working alone, we need to understand the work done by A and B together and B alone.

Let's assume the total time required to complete the job is T hours.

When A and B work together for 4 hours, they complete 100% of the work. So, the work done by A and B together is 100% of the job.

When B works alone for 4 hours, he completes 25% of the work. So, the work done by B alone is 25% of the job.

Since A and B complete 100% of the job together in 4 hours, we can say that their combined work rate is 100%/4 = 25% per hour.

Now, if B completes 25% of the job alone in 4 hours, his work rate is 25%/4 = 6.25% per hour.

Since A and B's combined work rate is 25% per hour and B's work rate alone is 6.25% per hour, A's work rate alone must be 25% - 6.25% = 18.75% per hour.

To find the time required for A to complete the whole job when working alone, we can set up the equation:

A's work rate alone * Time taken by A = 100% (the whole job).

18.75% * Time taken by A = 100%

Time taken by A = 100% / 18.75% = 5.33 hours.