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Question
The following are weights (in kg) of 12 people.
70, 62, 54, 57, 62, 84, 75, 59, 62, 65, 78, 60.
- Find the mean of the weights of the people.
- How many people weigh above the mean weight?
- Find the range of the given data.
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Solution
a. The weights of 12 persons are 70, 62, 54, 57, 62, 84, 75, 59, 62, 65, 78 and 60.
Sum of weights of 12 people
= 70 + 62 + 54 + 57 + 62 + 84 + 75 + 59 + 62 + 65 + 78 + 60
= 788
Number of observations (persons) = 12
∴ Mean = `"Sum of all observations (weight of 12 persons)"/"Number of observations"`
= `788/12`
= 65.66
b. Weights above 65.66 are 70, 84, 75 and 78, i.e. 4 persons.
c. Range = Maximum observation – Minimum observation
= 84 – 54
= 30
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