Biology - Uncertainty
posted by Stuck .
I'm doing a bio lab, and I have collected data on heart rate measured in beats/15 secs with an uncertainty of +/- 1 beat/sec. To get heart rate per minute, I multiplied my data by 4, making my uncertainty +/- 4 beats/min. However, what I need to do now is some subtraction, but my uncertainty ends up being much too large...for example:
(72 beats/min +/- 4 beats/min) - (68 beats/min +/- 4 beats/min) = (4 beats/min +/- 8 beats/min)
Have I done this correctly? Is it even possible to have uncertainty larger than the actual value? Thanks!