SOLUTION: Let x denote the time it takes to run a road race. Suppose x is approximately normally distributed with a mean of 190 minutes and a standard deviation of 21 minutes. If one runner

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Question 924192: Let x denote the time it takes to run a road race. Suppose x is approximately normally distributed with a mean of 190 minutes and a standard deviation of 21 minutes. If one runner is selected at random, what is the probability that this runner will complete this road race in less than 217.51 minutes?

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
mean of 190 minutes and a standard deviation of 21 minutes
*Note: z+=+blue%28x+-+190%29%2Fblue%2821%29
P(x < 217.50) = P( z < 27.5/21) = P(z < 1.3095) = normalcdf(-100,1.3095)