Smartphones: A poll agency reports that 40% of teenagers aged 12-17 own smartphones. A random sample of 125 teenagers is drawn. Round your answers to at least four decimal places as needed. Part: 0 / 6 Part 1 of 6 (a) Find the mean JA. P The mean un is XSAT scores: Assume that in a given year the mean mathematics SAT score was 524, and the standard deviation was 118. A sample of 66 scores is chosen. Use Excel. Part: 0/5 Part 1 of5 (a) What is the probability that the sample mean score is less than 509? Round the answer to at least four decimal places. The probability that the sample mean score is less than 509 is l l. X 5)