Write the following sets in roster form:
The set of first five odd counting numbers

Hint:
Here, we will use the concept of roster form to answer the question. Firstly we will find the first five odd counting numbers. Odd numbers are those numbers which are not divisible by 2. Then we will write these five numbers in the roster form.

Complete step by step solution:
We know that the counting numbers are the natural numbers which are the positive integer numbers.
Odd numbers are the numbers which are not divisible by 2.
Therefore the first five odd counting numbers will be 1,3,5.7,9.
Now we will write this in the roster form.
Roaster form is the representation of the set which shows the list of all the elements in that set separated by commas within the braces
Roaster form is represented as \[A:\left\{ {a,b,c} \right\}\]
Therefore,
Roster form of the set of first five odd counting numbers is \[A:\left\{ {1,3,5,7,9} \right\}\]

Hence, \[A:\left\{ {1,3,5,7,9} \right\}\]is the roster form of the set of first five odd counting numbers.

Note:
We should also know that integers are the numbers which can be positive or negative but integers can never be in fractional form or decimal form.
Natural numbers are the positive integer numbers. Even numbers are any integer that can be divided exactly by 2 is an even number. The last digit is 0, 2, 4, 6 or 8.
Terminating decimals are those decimal numbers that contain a finite number of digits after the decimal point. Non-terminating repeating decimals are those decimal numbers that contain an infinite number of digits repeating itself again and again after the decimal point.