So we have ratio 5/7, and sum is 168, so clearly numbers are not 5 and 7 since 5 + 7 = 12, not 168, so ratio is 5x / 7x, where x is unknown number.
So now we can set up sum: 5x + 7x = 168
12x = 168
x = 168 / 12 = 14
So our two numbers are 5x and 7x, which are 5 * 14 = 70 and 7 * 14 = 98
So the answer is 70 and 98