1. Always spell out simple fractions and use hyphens with them.
Examples: One-half of the pies have been eaten.
A two-thirds majority is required for that bill to pass in Congress.
2. A mixed fraction can be expressed in figures unless it is the first word of a sentence.
Examples: We expect a 5 1/2 percent wage increase.
Five and one-half percent was the maximum allowable interest.
3. The simplest way to express large numbers is best. Round numbers are usually spelled out. Be careful to be consistent within a sentence.
Correct: You can earn from one million to five million dollars.
Correct: You can earn from five hundred to five million dollars.