SOLUTION: Q. In a massive attempt to compete with General Electric, the Acme light bulb company issued a new line of bulb. Acme took 100 bulbs from their new line, which had standard deviati

Algebra ->  Probability-and-statistics -> SOLUTION: Q. In a massive attempt to compete with General Electric, the Acme light bulb company issued a new line of bulb. Acme took 100 bulbs from their new line, which had standard deviati      Log On


   

Question 1159094: Q. In a massive attempt to compete with General Electric, the Acme light bulb company issued a new line of bulb. Acme took 100 bulbs from their new line, which had standard deviation of 140 hours. The mean measured lifetime was 1280 hours. Give 95 % C.I for the mean lifetime of Acme' bulbs.
Use level of significance as 5%.
Found 2 solutions by Boreal, Alan3354:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
half-interval is a t(0.975 df=99)*s/sqrt(n)
=1.98*140/sqrt(100)
=27.72
the interval is added to and subtracted from the mean
(1252, 1308) units hours

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Q. In a massive attempt
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massive - a lot of mass/weight.
How much did the attempt weigh?