"Learning is the only thing the mind never exhausts, never fears, and never regrets."  (Leonardo Da Vinci)
Mathematical Drought in Western World (500  1200): The Islamic world was mathematically active during this period, as was the Hindu world. Perhaps the greatest of the Hindu mathematicians was Bhaskara (1114  1185), who, among many other things, produced several approximations for the number pi, including the frequently used 22/7. "It is remarkable to what extent Indian mathematics enters the science of our time. Both the form and the spirit of the arithmetic and algebra of modern times are essentially Indian and not Grecian."  (Florian Cajori) 
Answer: A practical choker. Herky 's friends: PATTY O'FURNITURE ... young lady who sells chairs that are used outside the house. BILL DING ... a contractor. 
Reading: Section 3.1, pages 113  120. Exercises: 3.8, 3.9, 3.10, 3.11.

You are in Section 3.1.
It is suggested that you look at pages 189  190in The Cartoon Guide toStatistics.
A very important thought that you should alwayskeep in mind: While there may be a fairly obvious relationshipbetween two variables, it does not follow that one causes the other.Association does not implycausation.
The TI83 can produce scatterplots. If you havexvalues in list L1, and yvalues in list L2, and have the samenumber of items in each list, then you can get a scatterplot usingSTAT PLOT. The first option under TYPE is a scatterplot. Make sureyou have L1 in Xlist and L2 in Ylist. Then ZOOM 9, which is ZoomStat,will show you a nice scatterplot. Some things to explore. Becurious!
What happens if you have L2 in Xlist and L1 in Ylist?
What happens if your two lists do not have the same number ofitems? (After you do a successful scatterplot, add a number to one ofyour lists, and then try to construct a scatterplot.
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Text:
The Practice of Statistics, by Yates, Moore, McCabe. New York,W.H. Freeman and Company, 1999. (ISBN 0716733706)
Supplemental books:
The Cartoon Guide to Statistics, by Gonick and Smith. NewYork, HarperCollins Publishers, 1993. (ISBN 0062731025)
How to Lie with Statistics, by Darrell Huff. New York, W.W.Norton & Company, 1982 (ISBN 039309426X)