An integer is a number that has no fractional part, and no digits after the decimal point. An integer can be positive, negative or zero. (Compare this to real numbers than can have digits after the point and can have fractional parts)

Example integers: 12 , 34 , -4 , 0

The following are real numbers and are not integers:

1.23 (cannot have decimal places)

12½ (cannot have a fractional part).

Drag the orange dab beneath to move it along the number line. Note how it just stops at the whole numbers.

Whole numbers and counting numbers

Whole numbers (here and there called ‘tallying numbers’) resemble whole numbers, yet they can’t be negative. They are typically used to show the number of items. Model: 12 understudies.

Rounding

Genuine numbers can be changed over to whole numbers by adjusting. This implies expelling the decimal digits and modifying the outcome to be the closest whole number to the first number.