Final answer:
To find the gain or loss percent, we need to understand the relationship between the cost price and selling price of the articles. According to the given information, the cost price of 10 articles is equal to the selling price of 7 articles. Using the equation 10C = 7S, where C is the cost price and S is the selling price, we can determine that there is a gain of 40%. The correct answer is (b) 40%.
Step-by-step explanation:
To solve this problem, we need to understand the relationship between the cost price and selling price of the articles. Let's assume that the cost price of one article is C and the selling price is S. According to the given information, the cost price of 10 articles is equal to the selling price of 7 articles, so we can write the equation 10C = 7S.
To find the gain or loss percent, we need to compare the selling price to the cost price. If the selling price is greater than the cost price, then there is a gain. If the selling price is less than the cost price, then there is a loss.
Using the equation 10C = 7S, we can rewrite it as C = (7/10)S. This means that the cost price is 7/10 times the selling price. Now, let's compare the cost price to the selling price:
- If C > S, there is a loss.
- If C = S, there is no gain or loss.
- If C < S, there is a gain.
Since C = (7/10)S, we can see that C is less than S, so there is a gain. To find the gain percent, we can subtract the cost price from the selling price and divide by the cost price:
Gain percent = ((S - C) / C) * 100 = ((S - (7/10)S) / (7/10)S) * 100 = ((3/10)S / (7/10)S) * 100 = (3/7) * 100 = 42.86%
Therefore, the correct answer is (b) 40%.