Discussion:
Q: A random sample of students who took the SAT college entrance exam twice found that 427 of the respondants had paid for coaching courses and that the remaining 2733 had not. Give a 99% confidence interval for the proportion of coaching among students who retake the SAT.
Use the following four step process:
STATE: What is the practical question that requires estimating a parameter?
PLAN: Identify the parameter, choose a level of confidence, and select the type of confidence interval that fits your situation.
SOLVE: Carry out the work in 2 phases:
1. Check the conditions for the interval you plan to use.
2. Calculate the confidence interval.
CONCLUDE: Return to the practical question to describe your results in this setting.