What is the z-score corresponding to P86 z = IMPORTENT----> three decimal places

The distribution of IQ scores of the population is normally distributed with a mean of 100 and a standard deviation of 15 for a particular data value. Since the population is normally distributed all sampling distributions will also be normally distributed. Find the z-scores for each of the following. Make sure to pay attention to the distribution you should use. Write exact answers as decimals. A single person with an IQ of 121: Z-score = Mean of a sample of 4 IQ's is 121: Z-score = 2.80 Mean of a sample of 9 IQ's is 121: Z-score = 1.40 Mean of a sample of 25 IQ's is 121: Z-score = 4.20 Mean of a sample of 100 IQ's is 121: Z-score = Mean of a sample of 625 IQ's is 121: Z-score = 7.00 14.00 35.00

Before every​ flight, the pilot must verify that the total weight of the load is less than the maximum allowable load for the aircraft. The aircraft can carry 42 ​passengers, and a flight has fuel and baggage that allows for a total passenger load of 7,056 lb. The pilot sees that the plane is full and all passengers are men. The aircraft will be overloaded if the mean weight of the passengers is greater than 7,056 lb42=168 lb. What is the probability that the aircraft is​ overloaded? Should the pilot take any action to correct for an overloaded​ aircraft? Assume that weights of men are normally distributed with a mean of 178.3 lb and a standard deviation of 36.8.

Suppose X ~ N(3, 1.2). What value of x is two standard deviations to the right of the mean?