Dropping Land

Grade level: 4 – 5th

Skills: Range

Related environmental issues: Excessive Water Extraction 

Area level: Regional (Southwest)

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Excessive pumping of groundwater for drinking and agricultural purposes often results in the land to drop. The table shows how many feet the land-surface elevation became lowered as a result of pumping water in nine area.

  1. Which area has the land dropped the most?
  2. How many more or less feet did the land in West of Phoenix (Arizona) dropped than the land in Houston (Texas)?
  3. What is the range of the set of the numbers in the table?
  4. What is the mode of the set of the numbers in the table?
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It shows how much the land dropped in the San San Joaquin Valley, California

Source: US Geological Survey

Photo: US Geological Survey


Answer keys

  1. Southwest of Mendota, California
  2. 9 feet more (18-9=9)
  3. 28 (29-1=28)
  4. 6