In: Math
A typical adult's resting heart rate is 79 BPM with a standard deviation of 12. If the heart rate of 9 randomly selected adults are taken, what average heart rate is at the 75th percentile? Round answer to 1 decimal place (i.e. 10.2)
Given that,
mean = = 79
standard deviation = = 12
n = 9
= 79
= / n = 9 /12=2.5981
Using standard normal table,
P(Z < z) = 75%
= P(Z < z) = 0.75
= P(Z <0.67 ) = 0. 75
z = 0.67
Using z-score formula
= z * +
=0.67 *2.5981+79
= 80.7