Sampling & Inference Worksheets Grade 11

1. Olivia is studying smartphone usage patterns among high school students. She stands outside the school library and surveys every 5th student who enters. Out of 150 students surveyed, 120 own smartphones. The total school population is 750 students. Based on her sample, what is the estimated number of smartphone owners in the entire school?
2. Liam is conducting a survey about high school students' study habits. He stands outside the school library and asks every 5th student who enters about their study time. Out of 1000 students at the school, he surveys 40 students. What percentage of the total student population did Liam survey?
3. Olivia is conducting a survey about high school students' screen time habits. She stands outside the school library and asks every 5th student who enters to complete her survey. Out of 850 students at the school, she collects 85 responses. What percentage of the student population is represented in Olivia's sample?

…and 3 more problems

1. Noah is conducting a study about smartphone usage patterns at his high school. He stands outside the school library and surveys every 6th student who enters between 3:00 PM and 4:00 PM. Out of the 121 students who visited the library during this time, he surveyed 16 students. Which statement best describes the potential bias in Noah's sampling method?
2. Mason is conducting a survey about high school students' study habits. He randomly selects 120 students from the 1500 students at his school and finds that 78 of them use a specific study app. Based on this sample, what is the estimated number of students in the entire school who use this study app?
3. Ava is studying geometric patterns and creates a sequence of nested squares. The largest square has side length 16 cm. Each subsequent square is inscribed by connecting the midpoints of the previous square's sides, creating a smaller rotated square inside. If this process continues infinitely, what is the total area of all the squares combined?

…and 2 more problems

1. Sophia is conducting a survey about smartphone usage among teenagers in her city. She stands outside a popular electronics store on a Saturday afternoon and asks every sixth person who enters the store to complete her survey. Which statement best describes the potential sampling bias in Sophia's method?
2. Sophia is studying the sampling method for a survey about smartphone usage. She notices the survey was conducted by calling landline phones between 9 AM and 5 PM on weekdays. If the population of interest is all adults aged 18-65 in the city, what percentage of the population is likely to be systematically excluded due to this sampling method? Assume that 31% of adults in this age group do not have landlines and 46% are typically at work during these hours, and that these groups overlap by 16%.
3. Mason is analyzing a triangular arrangement of dots. The first row has 7 dots, the second row has 9 dots, and each subsequent row has 2 more dots than the previous row. If there are 12 rows total, how many dots are in the arrangement?

…and 3 more problems