The amount of time a certain brand of light bulb lasts is normally distributed with a mean of 1200 hours and a standard deviation of 35 hours. Using the empirical rule, determine what interval of hours represents the lifespan of the middle 68% of light bulbs.

(1165, 1235) (hours)

Step-by-step explanation:

The "middle 68%" of a set of normally distributed data is that data that lies within ONE standard deviation of the mean:

(1200 - 35, 1200 + 35), or

(1165, 1235) (hours)

This is an application of the Empirical Rule.

answer: translate the circles so they share a common center point and dilate circle y by a scale factor of 3.