Quandaries and Queries


When one knows the
percentage, and a known number, how is the unknown total figured? In other words, I know that $14k is 22% of              what number??
This just escapes me.



I like the way you have written your question

$14k is 22% of             

It's almost an equation. If you use the fractional meaning of percent, (22% is 0.22) and realize that "of" is multiplication (25% of 200 is 0.25 times 200 which is 50), then your question is

14,000 = 0.22 (unknown), so
(unknown) = 14,000/0.22 = 63,630.

I never remember the formula, and I always resort to the fractional meaning of percentages and a little algebra. I notice that many, perhaps most people have problems with percentages, so without algebra the numbers they represent are a little hard to grasp. Therefore what surprises me most is that percentages are used so much in the press where simple numbers would suffice. I was reading the other day that the life expectancy in my town is 1.8% below the national aberage of 78.4 years; but I don't think many readers, or even the reporter, knew that it meant that the life expectancy in town was 77.0 years.

Claude and Penny


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