Question 266768
7.64 Jim’s systolic blood pressure is a random variable with a mean of 145 mmHg and a standard deviation of 20 mmHg. 
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For Jim’s age group, 140 is the cutoff for high blood pressure. 
(a) If Jim’s systolic blood pressure is taken at a randomly chosen moment, what is the probability that it will be 135 or less?
P(0<= 135)) = normalcdf(0,135,145,20) = 0.3085
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(b) 175 or more?
P(x>= 175) = 1 - normalcdf(0,175,145,20) = 1- 0.9332 = 0.0668
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(c) Between 125 and 165?
I'll leave this to you.
I get 0.6827
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(d) Discuss the implications of variability for physicians who are trying to identify patients with high blood pressure.
Discussion topic for you.
Cheers,
Stan H.