40 persons take 30 days to complete a work. How long will it take to complete the work, if
20 more persons join them?
Answers
Answer:
20 men takes 30 days to complete a job. So,
More men will take less days while Less men will take more days (common sense- no maths involved)
In our case it is more men i.e. 25 men thus as per above rule it will take less time than 30 days. The count of 30days can be reduced if multiplied by any value less than 1. (simple maths involved)
The multiplicant will be supplied by the data provided for number of men involved in two scenarios and this to be less than 1 should be like this 20/25 (low numerator and high denominator)
So, the answer should be (20/25)*30=24 days
P.S. It might seem lengthy process to get to the result but once the concept behind this is cleared , only the last equation will be in writing and all above would be just a mind game.