Homework 5 Equations and Answers

Example: Compare the results from questions 8 and 9. Explain why there is such a discrepancy (be specific in your response)

Answer for 8: 5.59% Answer for 9: 13.35% Comparing the Two: When comparing answers 8 and 9 in the homework you see that all the variables given are the same (both µ=500 both ơ=90). the difference is that the n's are different. In question n=51 and in question 9 n=25. When changing the sample number to a larger variable you're making the answer more accurate because you're taking a larger sample and recieving more information about the given task.

Example: µ=500, ơ=90 n=25 which is the probability that the sample mean would be less than 480?

answer: z=1.11 13.35%

Example: µ=500, ơ=90 n=51 which is the probability that the sample mean would be less than 480?

answer: z=1.59 5.59%

Example: µ=20, ơ=5 n=20 which is the probability that the sample mean would be greater than 22?

answer: z=1.79 3.67%

Example: µ=30, ơ=7 p(32<X<39)=

answer: 28.74%

Example: µ=80, ơ=20 p(X>75)=

answer: 59.87%

Example: µ=58, ơ=10 p(X<62)=

answer: 65.54%

Example: µ=100, ơ=20 what score will put an individual in the bottom 15% of the distribution scores?

answer: 79.2

Example: µ=75, ơ=6 p(63<X<84)=

answer: 91.04%

Example: µ=150, ơ=42 n=9 which is the probability that the sample mean would be greater than 185?

asnwer: z=2.5 0.62%

For the following, provide the appropriate raw scroes values, assuming the distribution is normal given: µ ơ z

use the equation x=µ+zơ

Calculate the probability value for each of the following situations, assuming the distribution is normal given: µ ơ x

use the equation z=((x-µ)/ơ)

For the following, a random sample is taken from the specific population (which is normally distributed) given: M µ n ơ

use the equation z=(M-µ)/(ơ/(√n))