SAT scores: Assume that in a given year the mean mathematics SAT score was 407, and the standard deviation was 105. A sample of )9 scores is chosen. Use the TI-84 Plus calculator, Part 1 of 5 (=) What is the probability that the sample mean score is less than 43)? Round the answer to at least four decimal places. The probability that the sample mean score is less then 455 is Part 2 of 5 "b) What is the probability that the sample mean score is between 430 and 470? Round the answer to at least four decimal places. The probability that the sample mean score is between 430 and 470 is Part 3 of 5 (c) Find the 45 percentile of the sample mean. Round the answer to at least two decimal places. The 45 percentile of the sample mean is Part 4 of 5 (d) would it be unusual if the the sample mean were greater than 4997 Round answer to at least four decimal places. It (Choose one) v be unusual if the the sample mean were greater than 499, since the probability is Part 5 of 5 (e) Do you think it would be unusual for an individual to get a score greater than 4997 Explain. Assume the variable is normally distributed. Round the answer to at least four decimal places. (Choose one) w , because the probability that an individual gets a score greater than 499 isSmartphones: A poll agency reports that 387% of teenagers aged 12-17 own smartphones. A random sample of 120 teenagers is drawn. Round your answers to at least four decimal places as needed. Fart 1 of 6 (2) Find the mean Us The mean JA Is |33 Fart: 1 / 6 Fart 2 of 6 (b) Find the standard deviation J. X The standard deviation J. is Part: 2 / 6 Part 3 of a (c) Find the probability that more than 40%% of the sampled teenagers own a smartphone. The probability that more than 40%% of the sampled teenagers own a smartphone is Fart: 3 / 6 Part 4 of 6 (d) Find the probability that the proportion of the sampled teenagers .who own a smartphone is between 0.35 and 0.45. The probability that the proportion of the sampled teenagers who own a smartphone is between 0.35 and 0.45 is Part: 4 / 6 Part S of 6 (e) Find the probability that less than 45 %% of sampled teenagers own smartphones. The probability that less than 43 % of sampled teenagers own smartphones Is Fart: 5 / 6 Part 6 of G (f] Would it be unusual if less than 30% of the sampled teenagers owned smartphones? It [Choose one) 7 be unusual if less than 30%% of the sampled teenagers owned smartphones, since the probability is ]-Babies: According to a recent report, a sample of 300 one-year-old baby boys in the United States had a mean weight of 25.5 pounds. Assume the population standard deviation is G = 5.5 pounds. Part 1 of 3 (a) Construct a 99% confidence interval for the mean weight of all one-year-old baby boys in the United States. Round the answer to at least one decimal place. A 99% confidence interval for the mean weight in pounds of all one-year-old baby boys in the United States is 24.7
