In a study of exercise, a large group of male runners walk on a treadmill for 6
ID: 3252514 • Letter: I
Question
In a study of exercise, a large group of male runners walk on a treadmill for 6 minutes. Their heart rates in beats per minute at the end vary from runner to runner according to the N(105, 12.9) distribution. The heart rates for male runners after the same exercise have the N(137, 17) distribution. (Round your answers to two decimal places.) (a) What percent of the runners have heart rates above 142? (b) What percent of the nonrunners have heart rates above 142? You may need to use the appropriate Appendix Table to answer this question.Explanation / Answer
Answer:
a).
z value for 142, z =(142-105)/12.9 =2.87
P( x >142) = P( z >2.87)
=0.0021
b).
z value for 142, z =(142-137)/17 =0.29
P( x >142) = P( z >0.29)
=0.3859