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.
Confidence votes 114. Like the standard deviation, the interquartile range (IQR) is a descriptive statistic used to summarize the extent of the spread of your data. The IQR is the distance between the 1st quartile (25th percentile) and 3rd quartile (75th percentile). Q3 - Q1 = IQR. To find these numbers you must divide your data set in half, and find the median of each half and that will be your Q1 and Q3.