An Accounting Firm Is Planning for the Next Tax Preparation

Multiple Choice

An accounting firm is planning for the next tax preparation season. From last year's returns, the firm collects a systematic random sample of 100 filings. The 100 filings showed an average preparation time of 90 minutes with a standard deviation of 140 minutes. What is the probability of finding a sample mean less than 80 minutes?

A) 0.7143
B) 0.7625
C) 0.2375
D) 0.0180