The price of a first class postage stamp was raised from 37 cents to 39 cents on Jan. 8, 2006. The change followed the approval of a Postal Rate Commission recommendation to raise prices on all classes of mail approximately 5.4 percent.
The interquartile range (IQR) is a measure of variability, based on dividing a data set into quartiles. Quartiles divide a rank-ordered data set into four equal parts.he interquartile range (IQR) is a measure of variability, based on dividing a data set into quartiles. Quartiles divide a rank-ordered data set into four equal parts.
Interquartile range (IQR) is a measure of how the middle [math]50\%[/math] of data are spread around the median. If IQR is large, data are more spread out from the median, otherwise they are closer. In other words, discard the lower and upper [mat...