Calculating Percent Change
In the lab portion of this class, we often have to calculate percent change in order to compare treatments of an experiment. You will need to do this is the Osmosis and Diffusion Labs in future modules. Understanding when to use percent change is part of the challenge of these labs. Read the example below to understand why percent change might need to be compared.
If you lose or gain a few pounds, it is likely that it will not be a cause for concern. However, a few pounds for a house pet like a cat or dog could be dangerous. The weight loss or gain can be expressed as a proportion of the original weight. Calculating percentage change is useful when comparing experimental and control groups in experiments.
The equation of percent change can be easily employed to compare data sets:
(V2−V1) × 100=?
V1
There are websites that do this calculation for you. These types of calculators are a great resource for conversions and other standard calculations. Students need to know when, and which of these calculators to use.