Chapter 7. Tax consultants can typically finish filling out a Form 1040 for Tax returns in about 4.55 hours with a standard deviation of about 2 hours and this time taken follows a normal distribution. Tax-Returns Quick Company employs 8 consultants who claim to be experts at filling out Form 1040 for their clients. Let X represent the time taken by a Tax-Returns Quick Company consultant to finish Form 1040. Unless otherwise specified, round all answers to 2 places after decimal point. (HINT: You have to find the Standard error based on sample size in this problem).

1. Distribution of X can be written as: X ~ N( , ).
2. The probability (in % terms) that a consultant takes between 4 and 5 hours to complete a Form 1040 is %.
3. The 25th percentile (or first quartile) for the average time taken to complete Form 1040 is hours and the 75^th percentile (or third quartile) is hours.
4. Therefore, the IQR = hours