Hyphenating compound numbers
At the beginning of a sentence
When numbers begin a sentence, they are written out. Hyphenate these numbers from 21 to 99.
Thirty-six patients were seen in the clinic that day.
One hundred twenty-two people were killed in the train derailment.
Twenty-fifth through 40th percentile results are shown.
Fractions
Hyphenate fractions used as nouns or adjectives.
A two-thirds majority passed the resolution.
Three-fourths of the questionnaires were returned.
The scar measured 2-1/2 inches.
He estimated it was 3-1/4 hours to finish.
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