If the cost price of 50 articles is equal to the selling price of 25 articles, then the gain or loss percent is?\nOptions:\n(A) 16\n(B) 127\n(C) 12\n(D) 18\n(E) 100
Let's think step by step.
(E)
Percentage of profit = 25/25 * 100 = 100%.

So, the final answer is (E)