Answer: 6 dollars per kilogram
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Step-by-step explanation:
The mixed number 4 & 1/2 converts to the decimal form 4.5
The unit price is 27/(4.5) = 6 dollars per kilogram
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If you wanted, you can think of it like this ratio
4.5 kg : 27 dollars
Dividing both parts of that ratio by 4.5 will lead to
1 kg : 6 dollars