Q5 · 2024 · Technology-activeSimple familiar1 mark
QUESTION 5
The mass (g) of adult kookaburras in a certain region is normally distributed with a mean of 300 g and a standard deviation of 13 g. Select the correct statement about the mass of adult kookaburras.
(A)
34% are between 287 g and 313 g
(B)
68% are between 274 g and 326 g
(C)
95% are between 261 g and 326 g
(D)
99.7% are between 261 g and 339 g
WORKED SOLUTION
1 markAnswer D
ANSWER
D — 99.7% are between 261 g and 339 g
Worked solution
The empirical rule places about 99.7% of a normal distribution within of the mean. Here , i.e. 261 g to 339 g, so option D.
Selects option D.
Worked explanation by QCE Vault; correct option verified against the QCAA answer key.
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