The High School For Construction Trades, Engineering, and Architecture

• MATH MES43

• Check Your Understanding What do you want to be when you grow up? According a nationwide survey of a random sample of 1000 kids under the age of 12, some kids want to be a ninja, a dragon keeper, a dancing unicorn, and even an octopus. Fifty-five of the 1000 kids want to be a doctor. We would like to use this study to find a 98% confidence interval for the true proportion of kids who want to be a doctor. a. Identify the parameter of interest. The parameter of interest in the true proportion of 12 year old kids who want to be a doctor. b. Check if the conditions for constructing a confidence interval for p are met. The 10% condition is met because the 1000 kids that were under 12 chosen are approximately less than 10% of all children under the age of 12. c. Find the critical value for a 98% confidence interval. Then calculate the interval. Invnorm(0.98, 0, 1)=2.05 0.055+_2.05=2.105, -1.995