Time and Work
A works twice as fast as B. If B can complete a work in 18 days independently, the number of days in which A and B can together finish the work in:
(a.) 2 days
(b.) 6 days
(c.) 4 days
(d.) 5 days
(e.) None of thes
Please find the solution:
Let total work is 18 unit.
B can complete 1 unit work in 1 day.
So, A can complete 2 unit work in 1 day.
One day work of A and B = 1 + 2 = 3 unit.
Required days to complete 18 unit by A and B both = 18/3 = 6 days.
The correct Answer is B.
Please solved this question. This question was asked in Cat 2017 in slot- 1
A person can complete a job in 120 days. He works alone on Day 1. On Day 2, he is joined by another person who also can complete the job in exactly 120 days. On Day 3, they are joined by another person of equal efficiency. Like this, every day a new person with the same efficiency joins the work. How many days are required to complete the job?
The efficiency of man is reduced by half every two hours.He could have completed the work in 150 hours at maximum efficiency.How many hours does he take if his efficiency becomes maximum after every 8 hours and then reduces as mentioned above?
Please find the solution below.
At maximum efficiency, he finishes the work in 150 hrs that means the amount of work done in 2 hrs at maximum efficiency = 1/75.
For next two hours he finishes = 1/150 amount of work.
In next two hours he does = 1/300 amount of work and
in another two hours, he finishes = 1/600 amount of work.
That means in total 8 hrs he does = (1/75)(1 + 0.5 + 0.25 + 0.125) = 1.875/75 = 1/40 amount of work.
As he regains his maximum efficiency after every 8 hrs, he does the same amount of work in every 8 hrs span.
So total time required to complete the work = 8*40 = 320 hrs.
A worker working under a bonus scheme saves 10 hours in a job for which the standard time is 60 hrs. A bonus of 10% of the hourly rate is payable when he reaches 100% efficiency. An additional bonus of 2% of the hourly rate for each 1% in excess of 100% efficiency is given. If the normal wage rate is Rs.2 per hour, find the wages payable to the worker.
A mother along with her two sons is entrusted with the task of cooking biryani for a family get together. It takes 30 minutes for all three of them cooking together to complete 50 percent of the task. The cooking can also be completed if the two sons start cooking together and the elder son leaves after 1 hour and the younger son cooks for further 3 hours. If the mother needs 1 hour less than the elder son to complete the cooking, how much cooking does the mother complete in an hour?
d. none of these
The efficiency of a man is reduced by half every two hours . At maximum efficiency, he could have completed the job in 150 hours . How how many hours does it take him to complete it the job , if his efficiency becomes maximum after every 8 hours and then reduces as mentioned above?
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