An office manager has received a report from a consultant that includes a section on equipment replacement. The report indicates that scanners have a service life that is normally distributed with a mean of 41 months and a standard deviation of 4 months.
On the basis of this information, determine the proportion of scanners that can be expected to fail within plus or minus 6 months of the mean.
(Enter your answer as a percentage without the percent sign; keep 2 decimal places)