1 The median is the middle value of the data set. 2  The lower quartile (Q 1) is the median of the lower half of the data set. 3  The upper quartile (Q 3) is the median of the upper half of the data set. 4  The interquartile range (IQR) is the spread of the middle 50% of the data values.
Removable Essix retainers typically cost between $100-$250 for one or $200-$500 for two. They are made from a vacuum sealed clear plastic that is less noticeable but more likely to break or warp, meaning that you could be paying the price more than once for this style of retainer.
Letâs break down some specific numbers when looking at industry averages and prices from Big Rentz, a major heavy construction equipment rental agency: Mid-range excavators weighing 15 to 20 tons generally range in price from $100,000 to $200,000 new (and can run up to $500,000 for larger customized models).