A variable measured at the interval or ratio level can have more than one arithmetic mean.
It is a HISTOGRAM.
He discovered the ratio of a perfect octave is 2:1.
He discovered the ratio interval of a perfect octave is 2:1.
intervals in degrees, nominal gender, ratio speed, ordinal grading
No, it is a ratio scale.
It is ratio.
interval
interval
ratio
Case number would be nominal scale; the number has no meaning.
interval
Nominal Scale < Ordinal< Interval < Ratio
Ratio. It has a true zero.
It is a ratio scale of measurement.
Ratio
It is on the interval scale.