To find the percentage of a number, you multiply the number by the percentage and then divide by 100. In this case, we are trying to find what percentage of 130 equals 78. So we can set up the equation (x/100) * 130 = 78, where x represents the percentage we are looking for. To solve for x, we can divide both sides of the equation by 130, giving us (x/100) = 78/130. By cross-multiplying, we get 130x = 7800, and dividing by 130, we find x = 60. Therefore, 60% of 130 is equal to 78.