Deriving Information from the Table
Having attribute information in table form allows you to obtain statistics, to search for specific text strings, and to sort the information.
____ 11. You can find out the average of the values of a column along with the count of the number of values, minimum, maximum, sum, and standard deviation.19 To do so, you right-click the column heading to bring up a menu of choices from which you choose Statistics. For example, select the column FLOW_RATE by placing the mouse pointer over the heading of the column (the pointer becomes a down-pointing arrow) and right-clicking. (You may have to use the scroll bar at the bottom of the table to find the FLOW_RATE column.) Choose Statistics from the drop-down menu. You see information about the values in the column from the Statistics of Fire_Hydrants window. There are 21 values. The minimum flow rate is 250. What is the maximum flow rate? ________. You also receive a frequency diagram that shows the number of hydrants that have each given value (e.g. there are four hydrants with a low flow rate, nine with a moderately high rate, and eight with a high rate). If all the hydrants were turned on at once, how much water would flow? __________. The mean (i.e., average) and standard deviation, although they probably don’t mean much in this situation, are about 356 and 54, respectively.
____ 12. Once you have the Statistics window up, you can determine the statistics of other columns by selecting the column ...

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