Question

Which ones are rational

1. 2.4





2. 74





3. 17.3333333…





4. π






5.





6. –18






7.

8. 87.125





9. –30





10. –8.3





11. 58.25







12. 121






13. 4.5





14.3 7/10

Answer 1

A rational number is a number that can be made by dividing two integers. An integer is a number that doesn't have a fraction part.

1. 2.4 - rational
2. 74 - rational
3. 17.3333333… - rational
4. π -irrational
5. there is no number
6. –18 - rational
7. there is no number
8. 87.125 - rational
9. –30 - rational
10. –8.3 -rational
11. 58.25 -rational
12. 121 -rational
13. 4.5 -rational
14. 3 7/10 -rational

As you can see, most numbers are rational. But, when you come across pi or when you have a decimal that goes on forever without repeating (like some square roots), it tends to be irrational.