passwella.
Menu

WAEC Mathematics 1997 Question 46

Question 46

Measures of Dispersion

Calculate the standard deviation of the numbers 2, 5, 6, 4 and 8

  1. A.2
  2. B.4
  3. C.6
  4. D.7
  5. E.20.
Show the answer and explanation

Answer: A (2)

Explanation

Mean = 25/5 = 5. Squared deviations: 9, 0, 1, 1, 9, total 20. Variance = 20/5 = 4, so the standard deviation is 2.