Tim Worker is doing his budget. He discovers that the average miscellaneous expense is $45.00 with a standard deviation of $16.00. What percent of his expense in this category would he expect to fall between $38.60 and $57.80?

The z for $38.60 = -.815.544.328.8.4.

The percent of area associated with $38.60 = .415.528.8.844.3%

The z for $57.80 = .828.844.3.415.5.

The percent of area associated with $57.80 = .8.415.528.844.3%

Adding the two together, the percent of his expenses between $38.60 and $57.80 is .428.844.3.815.5%