The problem asks us to find the gain percentage when a shopkeeper's gain is equivalent to the selling price (SP) of 40 pens, achieved after selling 200 pens.
The shopkeeper sold 200 pens. The profit (Gain) made is equal to the selling price of 40 pens.
Total SP for 200 pens = $200 \times S$.
Total Gain = SP of 40 pens = $40 \times S$.
We know that Gain = Total SP - Total CP.
Therefore, the Total CP for the 200 pens must be the SP of the remaining pens:
Total CP for 200 pens = Total SP for 200 pens - Gain
Total CP for 200 pens = $(200 \times S) - (40 \times S) = 160 \times S$.
This means the cost price of 200 pens is equal to the selling price of 160 pens.
The formula for Gain Percentage is:
Gain Percentage = $\frac{Gain}{Total CP} \times 100\%$
Substitute the values we found:
Gain Percentage = $\frac{40 \times S}{160 \times S} \times 100\%$
Cancel out $S$:
Gain Percentage = $\frac{40}{160} \times 100\%$
Simplify the fraction:
Gain Percentage = $\frac{1}{4} \times 100\%$
Gain Percentage = $25\%$
The gain percentage is $25\%$.
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A man sells a car to his friend at the loss of 10 %; who in return sells it for Rs. 54000 making a profit of 20 %. What was the initial value of the car?
An article was sold at a loss of 24%. If it were sold for Rs. 1,596 more, then there would have been a gain of 18%, The cost price of the article is:
The cost price of an article is Rs.6,450. If it sold at a profit 16%, how much would be its selling price?
If the selling price of 7 articles is equal to the cost price of 6 articles, then what is the percentage loss?