Juan Salvador just completed a study of the life expectancy of 100 light bulbs and discovered that the mean time that they lasted before burning out was 1,900 hours. If the standard deviation was 150 hours, the empirical rule allows Juan to conclude that approximately 68 of the bulbs burned out between _________ and _________ hours.
a. 1,750, 2,050
b. 1,800, 1,900.
c. 1,600, 2,200.
d. 1,450, 2,350.
The solution provides step by step method for the calculation of probability based on empirical relationship . Formula for the calculation and Interpretations of the results are also included.