Using proportions, it is found that the federal tax rate is of 10%.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
The tax rate is the <u>proportion that $17.50 is of $175</u>, hence:
r = 17.50/175 = 0.1 = 10%.
The federal tax rate is of 10%.
More can be learned about proportions at brainly.com/question/24372153
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