Question

Which subset of the real numbers does -18 not belong? Irrational, rational, negative #'s or integer

Answer 1

The natural numbers are also known as the counting numbers and consists of all the positive numbers: 1,2,3,4,5,....

Whole numbers (natural numbers plus zero): 0,1,2,3,4,.....

Integers (whole numbers plus the negative numbers): ......-4,-3,-2,-1,0,1,2,3,4...

As you can see above, one set builds on the other set. You can just memorize "NWI" to remember the order.

Irrational numbers consist of numbers that can't be written as fractions because they go on forever without repeating, such as: π, √5, etc.


Remember that zero is neither positive nor negative.


You may have figured it out by now that zero is part of the set of whole numbers and the set of integers.

Answer 2

Good Luck!

Answer 3

Recall -18 does belong to the set of rational numbers because $$\Huge -18=\dfrac{-18}{1}$$

Answer 4

There are infinite subsets of the real numbers :)