The price of the goods has been increased by 30%. By what percentage should it be lowered to get the original price?

Let’s denote by x the original price of the product. After the price of the goods was increased by 30%, the goods began to cost:
x + (30/100) * x = x + 0.3 * x = 1.3 * x.
In order to get the initial price, the price of the goods must be reduced by 1.3 * x – x = 0.3 * x, which in percentage terms is:
100 * 0.3 * x / 1.3 * x = 100 * 0.3 / 1.3 = 100 * 3/13 = 300/13 = 23 1/13.

Answer: in order to get the original price, the price of the product must be reduced by 23 1/13 (23 point and 1/13) percent.