Which of the following is an example of a rational number?

• A. π
• B. 3/5
• C. √2
• D. 2.718

Answer: (B)

A rational number is defined as any number that can be expressed as the quotient or fraction of two integers, where the denominator is not zero. The fraction 3/5 meets this criterion because it consists of two integers: 3 and 5. Both are whole numbers, and when you divide 3 by 5, you get a decimal that terminates (0.6), further confirming that it is rational.

In contrast, the other options represent numbers that do not meet the criteria for rational numbers. For instance, π is an irrational number that cannot be accurately expressed as a simple fraction. Similarly, √2 is known for being an irrational number, meaning it cannot be expressed as an exact fraction of two integers. Lastly, 2.718, although it may seem like it could be a rational number, actually represents the mathematical constant e which is also irrational. Thus, 3/5 stands out as the only example of a rational number among the choices.