Natural numbers are counting numbers or their equivalents:
1, 2, 3, 4, 5, 6 .......
Whole numbers are counting numbers and zero:
0, 1, 2, 3, 4, 5 ......
Integers are positive and negative whole numbers and zero:
..... -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5 .......
Rational numbers are numbers which can be written as fractions in the form p/q, where p and q are integers and q is not zero:
-5, 2, ¼, ½, 0.75, 1000, 0 .....
When written as decimals, rational numbers either terminate or recur.
Irrational numbers are numbers which cannot be written as fractions:
√2, √5, π
When written as decimals, irrational numbers do not terminate or recur. They go on for ever without repeating themselves.
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