Name: Josh Kuhar
Who is asking: Student
Level: Middle

How can you tell a number is rational?

Hi Josh,

If you can express the number as a fraction, that is an integer over an integer, then the number is rational, for example 3/5. If the number is in decimal form then it is rational if the same digit or block of digits repeats. For example 0.33333... is rational as is 23.456565656... and 34.123123123... and 23.40000...

If the digits do not repeat then the number is irrational.

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