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Usage and Grammar
Q. Is it correct to say, “The cost of the widget is 300 percent of its counterpart”? I’m wondering if this should be “The cost of the widget is 300 percent more than its counterpart.”
A. “Percent of” means something different from “percent more than.” It might be easier to understand if you use a different number: 50 percent of 100 people equals 50 people, whereas 50 percent more than 100 people equals 150 people. So although I can’t tell you the answer without knowing the cost of the widget and the cost of its counterpart, “300 percent of the cost” means three times the cost; “300 percent more than the cost” means the cost plus 300 percent of the cost (cost times 4). Since many people don’t know the difference, avoid those expressions and say exactly what you mean (e.g., “costs three times as much” or “costs $850 more than”).