Answer:
(c) $21,000
Explanation:
To find the amount of commission, multiply the commission rate by the value of the sale:
0.06 × $350,000 = $21,000
The agent earned a commission of $21,000.
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Additional comment
It may be helpful to remember that the % sign is fully equivalent to /100. That is, ...
6% = 6/100 = six hundredths = 0.06