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Asthma cases in Americans are about 75% higher today than they were in 1980.
The horizontal fraction bar was introduced by the Arabs.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
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