Answer:
Let’s outline the sets:
Integers: The collection of all whole numbers.
Rational: Numbers that can be expressed as the ratio of two integers.
Natural: The collection of positive integers.
Whole numbers: All the values obtainable by repeatedly adding (or subtracting) 1 to a number.
Thus:
2 qualifies as a:
Whole number, because 1 + 1 = 2 (therefore, it’s also an integer).
We can express 2 as 4/2.
As 2 is the fraction of two integers, it is also considered rational.
Since 2 is positive and an integer, it falls into the category of natural numbers.
Therefore, the number 2 exemplifies all four sets.
If we include a negative example, we can consider -3.
-3 is classified as an integer, is not a whole number, and with 9/-3 = -3, thus it is also a rational number.
Now, addressing the questions:
a) Although a single example can be used across all four sets, I have chosen 2 in this instance.
b) Similarly, I demonstrated that 2, as a positive integer, belongs to all four sets, thus:
Positive integers belong to:
The set of integers.
The set of natural numbers.
The set of rational numbers.
The set of whole numbers.
