Question

Assume that females have pulse rates that are normally distributed with a mean of mu equals 73.0 beats per minute and a standard deviation of sigma equals 12.5 beats per minute. Complete parts​ (a) through​ (c) below. a. If 1 adult female is randomly​ selected, find the probability that her pulse rate is less than 79 beats per minute. The probability is 0.6844 0.6844. ​(Round to four decimal places as​ needed.) b. If 16 adult females are randomly​ selected, find the probability that they have pulse rates with a mean less than 79 beats per minute. The probability is ----

Answer 1

Solution :

Given that,

mean = = 73.0

standard deviation = = 12.5

a ) P( x <79 )

P ( x - / ) < ( 79 - 73.0 / 12.5)

P ( z < 6 /12.5 )

P ( z < 0.48 )

= 0.6844

Probability = 0.6844

n = 16

= 73.0

= / n = 12.5 16 = 3.125

P( <79 )

P ( - / ) < ( 79 - 73.0 / 3.125)

P ( z < 6 /3.125 )

P ( z < 1.92 )

= 0.9726

Probability = 0.9726