Help with Search
Picture of Doug McG
Hints for HW14
by Doug McG - Wednesday, January 9, 2008, 07:32 PM
Another way of asking question 1 is, using the formulas for mean and standard deviation we discussed today (the proportion versions), what proportions (or percentages) are 2 standard deviations away if the mean is .6 and n = 200.

Don't get intimidated by the term "interval." It is just a name for low and high values along the horizontal axis for the area under the curve you are talking about.

For instance, in the diagram below, the 95% interval around the mean (40%) is between 10% and 70% (shown in red). The 68% interval would be between 25% and 55%.
Interval shown in reddish
Skip Navigation