In the number 51, there is only one 3. The digit 3 appears once in the number 51.
51/3 is 5.3333333333333333333333 (the 3s go on forever.)
28 3s
To find out how many 3s go into 140, divide 140 by 3. This gives you approximately 46.67. Since we're looking for whole 3s, you can fit 46 complete 3s into 140.
16
9
4
37.6666667
2,560
24 of them
There are: 21/3 = 7
3000/3 = 1000
203