We know that the blood pressure readings are made up with two values.
Systolic Blood pressure
Diastolic Blood pressure
The blood pressure readings are measured in millimeters of mercury (mmHg) and that the values are always in pairs. The scale of the pressure meter ranges from 0 to 300 (mmHg).
Now the blood pressure of a patient was recorded before and after the supplement.
From the information in Step 1 we can clearly say that the blood pressure is a type of continuous data. Hence, Begin and End are numerical(decimals) variables.
The pressure meter ranges from 0 to 300 (mmHg) which implies that the scale has true zero point. Hence the kind of scale are they following is a ratio scale.