Draw a picture. Draw a picture of a standard Normal curve and shade the tail areas to illustrate the calculation of the P-value for given Example.
Example
Comparing two sunblock lotions. Your company produces a sunblock lotion designed to protect the skin from exposure to both UVA and UVB radiation from the sun. You hire a testing firm to compare your product with the product sold by your major competitor. The testing firm exposes skin on the backs of a sample of 20 people to UVA and UVB rays and measures the protection provided by each product.
For 13 of the subjects, your product provided better protection, while for the other 7 subjects, your competitor's product provided better protection.