A Christmas tree light has an expected life of 200 hr and a standard deviation of 3 hr. Suppose 190,000 of these Christmas tree lights are used by a large city as part of its Christmas decorations. Estimate the number of lights that will require replacement between 185 and 215 hr of use.
A) 182,800
B) 7,600
C) 179,100
D) 7,000
E) 182,400

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The Answer of A Christmas tree light has an expected life of 200 hr and a standard deviation of 3 hr. Suppose 190,000 of these Christmas tree lights are used by a large city as part of its Christmas decorations. Estimate the number of lights that will require replacement between 185 and 215 hr of use.
A) 182,800
B) 7,600
C) 179,100
D) 7,000
E) 182,400

A Christmas Tree Light Has an Expected Life of 200