Which of the following is a rational number: 2π

, 6/0
, 61−−√
, or 0.37815?(1 point)

1 answer

A rational number is a number that can be expressed as the quotient of two integers (a fraction \( \frac{a}{b} \)), where \( b \) is not zero.

Let's evaluate the options provided:

  1. \( 2\pi \): This is an irrational number because \( \pi \) is irrational, and multiplying by a rational number (2) does not change that.

  2. \( \frac{6}{0} \): This is undefined because division by zero is not allowed. Therefore, it's not a rational number.

  3. \( \sqrt{61} \): This is also an irrational number because 61 is not a perfect square.

  4. \( 0.37815 \): This is a decimal number. It can be expressed as a fraction \( \frac{37815}{100000} \), which is a ratio of two integers. Hence, it is a rational number.

Considering all the options, the rational number is 0.37815.