4 3/4 is a mixed number because it consists of a whole number and a fraction.
Commutative is where you are able to move around the numbers to make it easier to add, subtract, divide, or multiply. Associative is where you can put parenthesis around any numbers and add, subtract, ect.
Answer:

Step-by-step explanation:
Given

i.e. first to fifth
Required
Determine number of selection
1st position = Any of the 30 students
2nd position = Any of the 29 students
3rd position = Any of the 28 students
4th position = Any of the 27 students
5th position = Any of the 26 students
Number of selection is then calculated as:

