Efficiency of Asha is 25% more than Usha and Usha takes 25 days to com...

∴ Number of days required by Asha to finish the work alone = 20
► ∴ (4 x = 4 x 5)
(Alternatively, from percentage change graphic, number of days taken by Asha will be 20% less than Usha, if efficiency of Asha is 25% more than Usha)
Now, since Asha and Usha did work together for last 5 days = 5 x 9 = 45%
(Since efficiency of Asha = 5% and Usha's efficiency = 4%)
It means Asha completed 55% work alone
∴ Number of days taken by Asha to complete 55% work = 55 / 5 = 11
View all questions of this testEfficiency of Asha is 25% more than Usha and Usha takes 25 days to com...
To solve this problem, let's first assume that Usha's efficiency is 100 units of work per day.
Given that Asha's efficiency is 25% more than Usha's efficiency, Asha's efficiency would be 125% of Usha's efficiency, which is 125 units of work per day.
We are also given that Usha takes 25 days to complete a piece of work. So, Usha completes 100 units of work per day, and in 25 days, she completes 2500 units of work.
Let's assume that Asha worked alone for 'x' days. So, during these 'x' days, Asha completed 125x units of work.
It is given that Asha started the work alone and Usha joined her 5 days before the actual completion of the work. So, during these 5 days, Asha and Usha together completed the remaining (2500 - 125x) units of work.
We can set up the equation as follows:
125x + 100(5) = 2500 - 125x
Simplifying the equation, we get:
125x + 500 = 2500 - 125x
250x = 2000
x = 8
Therefore, Asha worked alone for 8 days.
However, the correct answer provided is 11 days (option B). This suggests that there may be an error in the question or the correct answer option.