Question

The duration of routine operations at chicago general hospital has approximately a normal distribution with an average of 130 minutes and a standard deviation of 12 minutes. what proportion of operations last at least 120 minutes

Answer 1

79.77%

Explanation:

P(X≥120) = normalcdf(120,1e99,130,12) = 0.7976716754 ≈ 0.7977 = 79.77%

Therefore, about 79.77% of operations last at least 120 minutes