posted by Anonymous .
A market research company employs a large number of typists to enter data into a computer database. The time taken for new typists to learn the computer system is known to have a Normal distribution with a mean of 2.167 hours and a standard deviation 20 minutes. A candidate is automatically hired if he or she learns the computer system in less than 100 minutes. A cut off time is set at the slowest 40% of the learning distributions. Anyone slower than this cut-off time is not hired
This is what I did. I first converted 2.167 hours to minutes.
2.167 hours= 130.02 minutes
Then entered the data in my calculator
normalcdf (-e99, 100, 130.02, 20)
Thus the answer is B. Tell me if I'm right and if I'm wrong can you help me figure out what I did wrong and how to approach the right answer. Thank you :)