KAL LUZON SCHOOLS DIVISION OF ZAMBALES ALES NATIONAL HIGH SCHOOL ZONE VI, IBA. STATISTICS AND PROBABILITY 11 QUARTER 4 SUMMATIVE ASSESSMENT 1: Confidence Interval and Sample Size (Week 1) Prepared by: William Mhae F. Co General Directions: Write your answers on a separate yellow paper. A. WRITTEN WORKS. (10pts) Directions: Answer the following questions. (Show your complete solution to gain a point) 1. A survey of 200 Senior High School learners shows that they read on average 18.5 hours per week with a margin of error of 2.2 hours at a 95% confidence level. a. What is the lower limit? b. What is the upper limit? _. c. What is the confidence interval? _. d. If a student reads on average 15 hours per week, does it lies within the confidence interval? _. 2. A nutritionist is interested in monitoring the calorie intake of women. It was found that in a selected random sample of 50 female adults, the average daily intake of meat products is 2,200 calories per day with a standard deviation of 300 calorie. a. What is the margin of error? _ b. What is the length of the confidence interval? c. Construct a 99% confidence interval for j. . 3. The average weight of 25 chocolate bars selected from a normally distribute population is 200g with a standard deviation of 10 g. Find the interval estimates using 95% confidence level. 4. A officer is conducting an investigation in crime scene. He wanted to have a 95% confidence interval with a margin of error of 2 and a standard deviation of 8. a. How many respondents must he interview to achieve the desired result? b. Interpretation