MATH 10 – STUDY GUIDE FOR TEST ON CHAPTERS 6-7
1. If z is a standard normal variable, find the probability that z is …
less than -2.03
greater than -2.03
less than 0.87
greater than 0.87
between -1.4 and 2.17
between -1.4 and -0.39
between 1.08 and 2.85
2. The weight of soda in a "12 ounce" can is normally distributed with a mean of 12.24 oz and a standard deviation of 0.15 oz. What is the probability that the weight of soda in a randomly selected can will be less than 12 oz?
3. Use the continuity correction and describe the region of the normal curve that corresponds to the probability of "at most 15" [or, at least 15, or less than 15, or more than 15].
Would it be the area (to the right of, or to the left of) (14.5, or 15.0, or 15.5)?
4. For the binomial distribution, if n = ____ and p = ____ , is it suitable to use the normal approximation to approximate the binomial probability? (yes or no)
5. Given n = ____ and p = ____, use the normal approximation to the binomial distribution to calculate the probability of getting at least (or at most, or exactly) x = ______
6. Given a normal probability plot, determine whether the data comes from a normal distribution (yes or no)
7. Determine whether it is appropriate to use z, or t, or neither, if n = ____, s = ____ (or sigma = ____), and the distribution is bell-shaped (or skewed / non-normal)
8. Find the critical value za/2 that corresponds to a degree of confidence of ...
90%, or 93%, or 95%, or 98%, or 99%
9. Estimate a proportion: ____ people are surveyed, and it is found that ____ have red hair. What is the best point estimate of the true proportion of people in the population that have red hair?
10. Construct a 95% confidence interval for the proportion in problem 9 above
11. Find the minimum sample size to assure that your estimate of p will be within a margin of error of ____ with a confidence level of 95% (or some other level like 88%), with p unknown
12. Find a 90% (or 95%, or 98%...) confidence interval for estimating the population mean (sample over 30, sample mean ____, sigma known to be ___)
13. Find a 90% (or 95%, or 98%...) confidence interval for estimating the population mean (normal population, sample under 30, sample mean ____, sigma unknown, s = ___)
14. Find a 90% (or 95%, or 98%...) confidence interval for estimating the population mean (non-normal population, sample over 30, sample mean ____, sigma known to be ___)
15. Find a 90% (or 95%, or 98%...) confidence interval for estimating the population mean (non-normal population, sample over 30, sample mean ____, sigma unknown, s = ___)
16. Find the critical value ta/2: 95% (or some other level), n = ___, sigma unknown, population normal)
17. Find the critical values chi-square (left), chi-square (right) corresponding to a sample size of ___ and a confidence level of ___%
18. Find a confidence interval for a population standard deviation. Assume that the population has a normal distribution: ___% confidence, n = ____, x-bar = ____, s = ____
Return to: Merced College; Don Power Updated 11/03/09 by Don Power