Just divide.

0.583333. . .
^ This is the thousandths place
Look at the number after that, if it's 5 or more we round up, if it's 4 or less we round down.
It's 3, so we round down to 0.583.
<h3>
Answer: 2.4 pounds per dollar</h3>
Explanation:
We can set up the ratio
12 pounds : 5 dollars
Then divide both parts of that ratio by 5 so that the "5 dollars" becomes "1 dollar"
The ratio 12 pounds : 5 dollars is equivalent to 2.4 pounds : 1 dollar
√49 is a rational number.

Hope you could get an idea from here.
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