E

eighths

Eight parts of a whole that are the same size. A whole or group divided into eight equal parts or eight "fair shares." (See also fair share and one-eighth.)

equal parts

Pieces or parts of a whole that are the same size or amount. (See also fraction and fair share.)

equal sign

The symbol = shows that what is on the left of the sign is equal in value to what is on the right of the sign. For example, 2 + 2 = 4; 1 + 4 = 3 + 2.

equal to

Having the same value (=). For example, one nickel is equal to 5 pennies.

equals

The same amount or the same value. For example, 3 + 1 = 4.

estimate

1. To find about how many. For example, estimate how many beans in a jar.

2. An approximate number or a good guess. (See also benchmark numbers and friendly numbers.)

even

Numbers that have no leftovers if you make groups of two or two equal groups. Numbers that end with 0, 2, 4, 6, or 8.

exchange

To make a trade or changing one thing for another. For example, exchanging 1 nickel for 5 pennies.

expanded form

Shows a number expanded into its place value parts. For example, 300 + 40 + 2 is 342 in expanded form. This form can be used to add or subtract.