If a number can be expressed as a ratio of two integers with a nonzero denominator, it is called a...

If a number can be expressed as a ratio of two integers with a nonzero denominator, it is called a...

• A. rational number
• B. irrational number
• C. real number
• D. composite number

Answer: (A)

A number that can be written as a fraction of two integers with a nonzero denominator is called a rational number. This means you can find integers a and b (with b not equal to zero) such that the number equals a/b. Examples include 3/4, -5/2, and 0 (which can be written as 0/7). The idea is that the ratio of whole numbers captures exactly the rational numbers. Numbers like sqrt(2) or pi cannot be expressed as such a ratio, so they are irrational. The term real number covers both rational and irrational numbers, but the fraction form specifically identifies the rationals. A composite number, meanwhile, is just a kind of integer with more than two positive factors, which is unrelated to whether a number can be written as a fraction of integers.

A number that can be written as a fraction of two integers with a nonzero denominator is called a rational number. This means you can find integers a and b (with b not equal to zero) such that the number equals a/b. Examples include 3/4, -5/2, and 0 (which can be written as 0/7). The idea is that the ratio of whole numbers captures exactly the rational numbers. Numbers like sqrt(2) or pi cannot be expressed as such a ratio, so they are irrational. The term real number covers both rational and irrational numbers, but the fraction form specifically identifies the rationals. A composite number, meanwhile, is just a kind of integer with more than two positive factors, which is unrelated to whether a number can be written as a fraction of integers.