Question

A study found that the mean amount of time cars spent in​ drive-throughs of a certain​ fast-food restaurant was 159.7 seconds. Assuming​ drive-through times are normally distributed with a standard deviation of 32 ​seconds:

a) The probability that a randomly selected car will get through the​ restaurant's drive-through in less than 123 seconds is ____

b) The probability that a randomly selected car will spend more than 199 seconds in the​ restaurant's drive-through is _____

c) The proportion of cars that spend between 2 and 3 minutes in the​ restaurant's drive-through is ____

d) The probability that a car spends more than 3 minutes in the​ restaurant's drive-through is _______​, so it ______ (would/would not) be​ unusual, since the probability is ____ (greater/less) than 0.05.

Answer 1

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