Answer:
4 
<em><u>OR</u></em>
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Step-by-step explanation:
<em><u>I'm not exactly sure which type of fraction you're asking for, so I'll put both.</u></em>
This would be the fraction for 4.5 because the 0.5 is half of 1, while we already have a whole number, being 4.
<em><u>OR</u></em>
9 divided by 2 is 4.5, making the fraction for 4.5, 