Answer:
-31 is an integer, a rational number, and a real number.
Explanation:
The question is asking us to find which set the number -31 belongs in.
So let's take a look at all the sets of numbers first.
Natural Numbers: This set includes only positive numbers, not even zero.
Whole Numbers: This set overlaps a lot with natural numbers. The only difference is that this set does include zero.
Integers: This set is made of whole numbers and negative ones.
Rational Numbers: Here we have integers plus all fractions and decimals.
Irrational Numbers: This set includes numbers that cannot be expressed as fractions.
Real Numbers: This set includes ALL of the subsets listed above.
What kind of a number is -31? It's negative, so it can't be a natural number or a whole number. But it can be an integer, a rational number, and a real number.
∴ -31 is an integer, a rational number, and a real number.