To determine which numbers are irrational, we need to identify numbers that cannot be expressed as a simple fraction (i.e., the ratio of two integers). Here’s the classification of the options given:
- √16: This is 4, which is a rational number.
- π (pi): This is a well-known irrational number, as it cannot be expressed as a fraction of two integers.
- √12: This can be simplified to 2√3. Since √3 is irrational, √12 is also irrational.
- 1.7: This is a terminating decimal and can be expressed as a fraction (17/10), so it is rational.
- √80: This can be simplified to 4√5. Since √5 is irrational, √80 is also irrational.
- 7/18: This is a simple fraction and hence rational.
Based on this analysis, the irrational numbers from the list are:
- π
- √12
- √80
Therefore, the three numbers that apply are π, √12, and √80.