6.9. On a toy assembly line, daily output for each worker averages 46.7 units with a standard deviation of 8.90 units. Assume the histogram of daily output looks approximately like the normal curve. a. On a given day, what percentage of workers have a daily output over 50 units? b. 25 workers are selected at random. What is the probability that their output for a given day will average 50 units or higher? 0. 25 workers are selected at random. There is an 80% chance that their output will average below units. Example The manager of the local branch of a bank determines that 40 percent of all depositors have multiple accounts at the bank. If you select a random sample of 200 depositors, what is the probability that the sample proportion of depositors with multiple accounts is less than 0.30? Solution: We know that the sample proportion follows the normal distribution with mean 0.4 and standard error 0420004) = 0.0346. As such, the probability that the sample proportion of depositors with multiple accounts is less than 0.30 is normalcdf(-E99, 0.3, 0.4, 0.0346) = 0.0019