2024 RI H1 Q6
2024 RI H1 Q6
4 marks
The lifespan, \(L\) (in months) of the battery in a certain brand of handphone is normally distributed. It is known that \(21\%\) of the batteries last for more than \(26\) months and \(34\%\) of the batteries last for less than \(23\) months. Find the mean and variance of \(L\).[4]
Solution:
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Answer:Mean \(24.0\) months; variance \(6.06\) months squared (3 significant figures).
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