Well, first you'd do..... 1x110=110 SO, 1 is a factor. 2x55=110 , SO 2 is a factor 3x nothing=36.66666, which means 3 is NOT a factor. So far, we have 1 and 2. Then you do four five...... So, the factors of 110 are... 1, 2, 5,10, 11, 22, 55, 110 you forgot 10 ^^^