MathsheetsPrintable math worksheets for teachers and families
NameDateTime:to:

Center or Spread?

One number for the middle, one for the spread — and say which does which job.

ExampleA survey of time spent on homework gave these values, in minutes:
14, 16, 16, 18, 18, 18, 20
Give one number that summarizes the middle of the data and one that summarizes how spread out it is. Say which is which. Center: the median is 18 minutes — a single number standing for a typical value. Spread: the range is 20 − 14 = 6 minutes — a single number saying how much the values differ. A center alone does not tell you whether the data is tightly packed or widely scattered.
  1. 1.Two classes both have a median of 15 minutes for time spent on homework. One class ranges from 12 to 20 minutes; the other ranges from 14 to 16 minutes. Are the two classes the same? Explain.
  2. 2.Two classes both have a median of 4 books for books read. One class ranges from 2 to 8 books; the other ranges from 3 to 5 books. Are the two classes the same? Explain.
  3. 3.Two classes both have a median of 3 pets for number of pets. One class ranges from 0 to 7 pets; the other ranges from 2 to 4 pets. Are the two classes the same? Explain.
  4. 4.Two classes both have a median of 129 seconds for song length. One class ranges from 121 to 130 seconds; the other ranges from 128 to 130 seconds. Are the two classes the same? Explain.
  5. 5.Two classes both have a median of 11 cm for plant height. One class ranges from 6 to 15 cm; the other ranges from 10 to 12 cm. Are the two classes the same? Explain.