Well, there really isn't an equation for this. Just plug in numbers and see if the numbers have to be bigger or smaller than the one you guessed. In this case, after plugging in a couple of numbers, I plugged in 17 for the smaller number. Then to find the bigger number, I multiplied 17 by 3, which is 51, then subtracted 7 from 51, which is 44. Since 44+17=61, the numbers are 44 and 17.