An interval that does not include the end points.
Example: the interval (0,20) is all the numbers between 0 and 20, but not 0 or 20.
Could also be written 0 < x < 20
Imagine a company only accepts a package "less than 20 kg", so 20 kg is not included, nor is 0 kg because that is not a package: so 0 < package < 20 kg
Example: the interval (0,20) is all the numbers between 0 and 20, but not 0 or 20.
Could also be written 0 < x < 20
Imagine a company only accepts a package "less than 20 kg", so 20 kg is not included, nor is 0 kg because that is not a package: so 0 < package < 20 kg
See: Closed Interval
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