4.5 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its equivalent, in rational form, is 9/2. So the answer is 9/2 hours.
It is 9/2.
0.2222
2/9
It is: 4.5 = 9/2 as an improper fraction
2/9
5
2.25 is a fraction. It is a fraction in decimal form rather than in the form of a ratio. However, that does not stop it being a fraction. Its equivalent, in rational form, is 225/100. You can simplify this rational fraction if you require.
No fraction has "its simplest form" as 6/9. That is because any fraction that is equivalent to 6/9 can be further simplified to 2/3.
45 is an integer, not a fraction.
2/9
9 is an integer and not a fraction.