SOLUTION: The average cost of repairing an iPod is $120 with a standard deviation of $10.50. The costs are normally distributed. If 15% of the costs are considered excessive, find the cos

Algebra ->  Probability-and-statistics -> SOLUTION: The average cost of repairing an iPod is $120 with a standard deviation of $10.50. The costs are normally distributed. If 15% of the costs are considered excessive, find the cos      Log On


   



Question 1161602: The average cost of repairing an
iPod is $120 with a standard deviation of $10.50. The
costs are normally distributed. If 15% of the costs are
considered excessive, find the cost in dollars that would
be considered excessive.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Want the 85th percentile for costs with mean 120 and sd 10.50 (dollars are units)
Can use 2VARS 3 invnorm(.85,120,10.50) and get $130.88 .
This makes sense because +1 sd is 0.8417 so the 85th percentile should be about +1 sd or $130.50