Which of the following is a rational number: 2π, 60, 61−−√, or 0.37815?
The only number that is a rational number out of the given options is 60, since it can be expressed as a fraction (60/1).
A rational number is a number that can be expressed as a ratio of two integers. Let's examine each option to determine if it is a rational number:
1. 2π is not a rational number because π (pi) is an irrational number, which means it cannot be expressed as a simple fraction.
2. 60 is a rational number because it can be expressed as the ratio 60/1, which is a fraction consisting of two integers.
3. 61√ is not a rational number because the square root of 61 is an irrational number.
4. 0.37815 is a rational number because it can be expressed as the fraction 37815/100000, which is a ratio of two integers.
Therefore, out of the given options, only 60 and 0.37815 are rational numbers.