Question

The age in Australia has a normal distribution with a mean 45 years and standard deviation 11 years. The children are classified as the youngest 33% of population. At what age do children become adults in Australia

20
30
40
50

Answer 1

40 y/o

Explanation:

33% is a z-score of -.44

-.44 standard deviations

45 - .44(11) = ~40 y/o Seems an odd answer !