Readers generally find figures easier to understand than word expressions for numbers. Nevertheless, numbers should be spelled out in some instances.
For uses not covered by these listings, spell out whole numbers between zero and 10; use figures for 10
He has a fleet of five cars and 10 trucks.
SIM numbers style should be applied to all copy, even if it is quoted material.
incorrect: ”We insisted on nine-foot ceilings,” she says.
correct: “We insisted on 9-foot ceilings,” she says.
incorrect: ”I love the three-eighths-inch molding along the edge,” he says.
correct: “I love the 3/8-inch molding along the edge,” he says.
See also Dimensions, Measurements, and Sizes