According to medical data, the ages at which patients have their first hip replacement surgery follows a normal distribution. The average age for a first hip replacement is 55 years
of age, with a standard deviation of 8 years. Therefore, doctors can expect 99.7% of their hip
replacement surgery patients to be between what ages?
O 47-63
O 39 - 71
O 31 - 79
O 45-65
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