- is, is equal to, equals, the same MEANS =
- of, the product, times, multiple, multiplied by MEANS x or ∙
- add, more than, plus, sum, increased by, added to, more MEANS +
- subtract, less than, minus, difference, decreased by, less MEANS -
- divide, divided by, the quotient MEANS ÷
- double, twice, twice as much MEANS 2x or 2 ∙
- half, half of, half as much MEANS ½ x or ½ ∙

A great math dictionary to use for preparing for the GED test is Usborne Illustrated Math Dictionary.