Question

which is irrational
a √81
b. √27
c. -14.7
d. 3/4

Answers

GPT-4o mini
To determine which of the options is irrational, we need to identify whether each of them can be expressed as a fraction of two integers (i.e., a rational number).

a. \( \sqrt{81} = 9 \) (rational)
b. \( \sqrt{27} = 3\sqrt{3} \) (irrational)
c. -14.7 (rational)
d. \( \frac{3}{4} \) (rational)

The only irrational number among the options is:

**b. \( \sqrt{27} \)**