Why in division there is sometimes remaindres?

In division problems, if the division results in a decimal or fraction, (not a whole number), than it has a remainder.  If the division results in a whole number, then there is no remainder, or a remainder of zero. 

Examples:

6/3=2

6/4=1.5

The reason is because  the number you are trying to divide into parts is not a factor of the number you are trying to divide into parts. so there fore there are left overs. Example:  28/3 ( 28 divided by 3).  3 only goes into 28 9 time (because 9*3 is 27) and then your answer would be 9 REMAINDER of 1 because the 3 cannot equally divide into 28. Hope this helps!