noTh1ng wrote:

Can someone pls review my approach?

6 workers need 8 days for a job. This implies that one worker's rate is 8 / 6 = 4 / 3.

Rate of one worker = 4 / 3 times the new number of workers (6+4 = 10):

4/3 * 10 = 40/3 is the rate for all workers.

Take the reciprocal: 3 / 40 implies that they need 3 weeks for the work of 40.

Is this correct or did i just got lucky? Thanks!

You have made a sever mistake of this topic in the calculation you have shown

6 workers need 8 days for a job. This implies that one worker's rate is 8 / 6 = 4 / 3.The highlighted part is a flaw in your process. The correct Understanding of the highlighted part is as mentioned below

6 workers need 8 days for a job. This implies that one worker's rate is 8 * 6 = 48 days to finish the same jobThe reason for this interpretation is

Manpower is Inversely Proportional to the Time.

CONCEPT:i.e. more manpower causes less time to finish the job and Less manpower requires more time to finish the jobWork can be finished in 8 days

Remaining Days = 8-3 = 5 days

Now, 6 workers are joined by 4 more workers i.e. the Manpower Increases from 6 to 10 i.e. 5/3 of previous workforce

therefore New time taken should be reciprocal (Inversely Proportional) i.e. 3/5 of previous time i.e. New time = (5)*(3/5) = 3 daysSo they Require 3 more days to finish the work.

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