To which subset of real numbers does -3 belong?
a) integers
b) irrational numbers
c) integers and rational numbers
d) whole numbers, integers, and rational numbers

Explanation:

The set of integers is {..., -3, -2, -1, 0, 1, 2, 3, ...} basically any number that does not have a decimal or fractional part to it. We can say that this set is composed of positive and negative whole numbers along with 0. So this is why -3 is in the set of integers.

The value -3 is not in the set of whole numbers because the set of whole numbers is {0, 1, 2, 3, 4, 5, 6, ...}, so this rules out choice D.

Choice B is also eliminated because -3 is a rational number. We can write -3 as a fraction of two integers, example: -3 = -3/1. Any rational number is not irrational, and vice versa.

Choice A is ruled out because it's not the most complete answer (though its technically true).

.567

Step-by-step explanation:

The original ratio is 21:37

Any ratio is a fraction

A fraction is a division problem

Rewrite the ratio as a fraction : 21:31---> 21/31

Divide 21 by 31 and you get .567