6.3

1: Normal distributions are symmetrical about the mean.

3: Only 5% of the area under the curve lies to the left of z, and the rest of it lies to the right.

5: Find the z scores, shade between them, and find the shaded area by getting the areas from the table and subtracting.

14: See below the table for z values that are off the chart (like z = 4 in this case).

16: Convert 5.2% to a decimal so you can find it inside the table.

19: Look up the complement of 8% to find the area above 8%.

23: The middle 98% of the curve is 49% below the middle and 49% above the middle.

29: For (a), find the percentage for x = 36 months (see 6-B), and for (b), find the number of months x for the bottom 10% (see 6-C).

36: Convert 7200 and 8900 to z scores so you can look up their percentages.