Many Manufacturers of Light Bulbs Advertise Their 100 Watt Bulbs $\Sigma$

Essay

Many manufacturers of light bulbs advertise their 100 watt bulbs as having life of 750 hours (about a month). Suppose two electrically minded students wired up 10 bulbs so that the time was recorded when they burned out. The following statistics were obtained. Perform a t test, calculate the effect size index, and write a conclusion about the manufacturers' claim. $\Sigma$ X = 7400 $\Sigma$ X² = 5,479,600 N = 10