1959 AHSME Problems/Problem 9
A farmer divides his herd of cows among his four sons so that one son gets one-half the herd, a second son, one-fourth, a third son, one-fifth, and the fourth son, cows. Then is:
The first three sons get of the herd, so that the fourth son should get of it. But the fourth son gets cows, so the size of the herd is . Then our answer is , and we are done.