Mathematics IV Study Guide Fall 2013 Henry County Schools In Addition to these sample problems, students should review all previous test questions, class notes, and formative and summative assessments, etc. in preparation for this Exam Part I: Unit 2 (Sequences) Wednesday Part II: Unit 3 (Rational Functions) Thursday Part III: Unit 1 (Data Analysis) Friday Z-Score Table Z-Score Table c 0.50 0.60 0.70 0.80 0.90 0.95 0.96 0.98 0.99 0.995 0.998 0.999 zc 0.674 0.841 1.036 1.282 1.645 1.960 2.053 2.326 2.576 2.807 3.090 4.500 Calculator Cheat Sheet for Math IV – Unit 1 Assessment Students may use on assessment Finding confidence interval with a calculator if you know x, Sx , n, and c level Stat Tests 8 Stats Enter (stats must be highlighted) Enter Finding confidence interval without a calculator: Margin of Error: E zc xE xE Sx n x, Sx , n, and c level Enter twice Confidence interval in parentheses Putting data into the calculator: Stat 1 Calculating x, S x , n, min X , Q1 , Med , Q3 and max X Stat Calc 1 Enter Generating a random sample in a list (L1) Stat 1 L1 (should be highlighted) MATH PRB 5 randInt(13, 18, 10) Lowest number Highest number Sample size MM4D1: Using simulation, students will develop the idea of the central limit theorem. Simulating and Describing Data For problems 1 – 2 simulate collecting data by finding a random set of integers with the given parameters. Plot the sample set on a dot plot and describe the distribution of the data. 1. Twenty integers between 10 and 15, inclusive ___________________________________________________________________________________ dot plot 2. Thirty integers between 20 and 30, inclusive __________________________________________________________________________________ dot plot 3. A random set of integers is generated to simulate a data collection of integers from 50 to 55. Which set of data that follows could be the generated integers? a. { 50, 51, 51, 52.5, 55} b. { 51, 53, 55, 55, 56} c. {53, 54, 55, 55, 56} d. {54, 54, 54, 55, 55} 4. A sample of 100 data points is collected. The data is skewed to the left. Twenty more samples of data are collected, each with 100 data points. What is the distribution of all the data points? a. Normal b. Skewed to the left c. Skewed to the right d. Distribution is not certainly known 5. State the central limit theorem: _______________________________________________________________________________________________ _______________________________________________________________________________________________ _______________________________________________________________________________________________ _______________________________________________________________________________________________ 6. Which data set has a distribution that is skewed to the left? a. b. c. d. {1, 2, 3, 3, 3, 3, 3, 3, 4, 5} {14, 15, 15, 15, 16, 16, 17, 18, 21} {25, 25, 26, 27, 28, 29, 29, 30, 31} {32, 36, 38, 40, 41, 42, 43, 43, 44} MM4D2: Using student-generated data from random samples of at least 30 members, students will determine the margin of error and confidence interval for a specified level of confidence. 7. What is the margin of error of the mean of 50 data items with a standard deviation of 3.2? Use a confidence level of 90%. a. 0.11 b. 0.23 c. 0.74 d. 37.22 8. Determine the confidence interval, for a 95% confidence level, of the population mean for a set of data with a margin of error 1.9 and a sample mean of 18.3. a. -1.9 < m < 1.9 b. 16.4 < m < 20.2 c. 17.4 < m < 19.2 d. -16.4 < m < 20.2 9. What is the mean and standard deviation of the data set below? 35 48 27 36 16 23 37 37 40 42 42 17 32 39 34 39 36 23 19 47 45 25 20 30 44 46 35 17 25 24 17 47 46 24 41 37 45 29 36 37 Mean = _____________________ Standard deviation = __________________________ 10. What is the margin of error of the mean of 60 data items with a standard deviation of 1.4 and mean of 10.4? Use a confidence level o f99%. a. 0.060 b. 0.465 c. 9.935 d. 130.58 11. A set of data items with which confidence level and corresponding z-score would have a margin of error of 0.8375? The sample standard deviation is approximately 3.6. a. 90%; zc = 1.645 b. 95%; zc = 1.96 c. 90%; zc = 1.645 d. Cannot be determined MM4D3: Students will use confidence intervals and margins of error to make inferences from data about a population. Technology is used to evaluate confidence intervals, but students will be aware of the ideas involved. 12. What is the confidence interval for the population mean if the sample mean is 36.15, the sample standard deviation is 0.98, and the confidence level is 91%? There are 90 items in the sample data set. a. 35.17 < m < 37.13 -0.18 < m < 0.18 c. 32.90 < m < 39.40 d. 35.97 < m < 36.33 b. 13. A random selection of 200 wedding photographers was surveyed throughout the United States. The photographers were asked the base hourly rate they charged to photograph a wedding. With 92% confidence, the confidence interval of the population mean of the data was 98.10 < m <142.30 . Which statement that follows could be reasonably assumed of all wedding photographers in the United States? a. With 92% confidence, a wedding photographer will charge at least $98.00 per hour. b. With 92% confidence, the hourly rate of a wedding photographer will range between $98.10 and $142.30. c. No wedding photographers charge more than $142.30 per hour. d. All wedding photographers charge at least $98.10 per hour. 14. Which can be inferred about the population mean if the margin of error is 0.113, the sample mean is 4.2, the standard deviation is 0.51, the sample size is 55, and the confidence level is 90%? a. No more than 90% of the 55 data points are within 0.51 units of 4.2 b. It is 90% probable that the population mean is equal to 4.2 c. With 90% confidence, the population standard deviation is 0.51. d. With 90% confidence, the population mean is between 4.09 and 4.31. 15. What is the confidence interval for the population mean if the sample mean is 36.15, the sample standard deviation is 0.98, and the confidence level is 91%? There are 90 items in the sample data set.