Joggers 1 and 2 run. Jogger 1's mean run is 5.25 whereas Jogger 2's mean run is 4.20. What can we infer about Jogger 1 and 2? What can't we infer?

1 Answer
MathFact-orials.blogspot.com
Feb 16, 2017

We'd infer that Jogger 1 (mean #=5.25#) runs further than Jogger 2 (mean #=4.20#) by about one unit

Explanation:

The mean is calculated by adding the values and then dividing by the number of terms. For instance, the mean of 2, 3, 4 is:

#(2+3+4)/3=9/3=3#

From comparing the two means, we'd infer that Jogger 1 (mean #=5.25#) runs further than Jogger 2 (mean #=4.20#) by about one unit (perhaps kilometres? or miles?)

#(5.25-4.20=1.05)#

What don't we know?

  • how many times Jogger 1 and Jogger 2 have jogged. Maybe they've gone 100 times. Or maybe once.
  • how tightly to the means Jogger 1 and Jogger 2 stay. Do they both have a set track they run so that the distance never varies? Or is it that one day they run one unit and the next they run 10.
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