Question

15) Assume that z scores are normally distributed with a mean of 0 and a standard deviation 15) of 1. If P(z> c) 0.109, find c. olve the problem. 16) 16) Scores on an English test are normally distributed with a mean of 37.4 and a standard deviation of 7.9. Find the score that separates the top 59% from the bottom 41% 17) Suppose that replacement times for washing machines are normally distributed with a 17) mean of 10.9 years and a standard deviation of 1 years. Find the replacement time that separates the top 18% from the bottom 82% ind the indicated probability. 18) 18) The volumes of soda in quart soda bottles are normally distributed with a mean of 32.3 oz and a standard deviation of 1.2 oz. What is the probability that the volume of soda in a randomly selected bottle will be less than 32 oz?

Answer 1

(Question 15) Find c such that P(Z 〉 c) 0.1090 0.109 Since we use z-table with area to left of z, we want this equation in left-area form P(Z > c) 0.1090 . P(Z < c) 0.8910 (0.8910) is not present in the z-table containing area to left of z, but we can use linear interpolation.