To determine how many 3's go into 28, you would perform division. 28 divided by 3 equals 9 with a remainder of 1. Therefore, there are 9 whole 3's in 28.
210
35
22
100 of them
33.3333333 3's go into 100
100
13
27 threes are in 81
43 ÷ 3 = 14 with remainder 1
There are: 91/3 = 30 with a remainder of 1
33.33... the threes never will end.