Resting heart rate was measured for a group of subjects and then the subjects drank 250ml of
coffee. Ten minutes later their heart rates were measured again. The change in heart rate followed
a Normal distribution with a mean increase of 7.3 beats per minute and a standard deviation of
11.1. (a). A negative value for change in heart rate implies that the persons heart rate went down.
What proportion of people had heart rates that went down? (Hint: a heart rate change < 0)? (b).
99% of heart rate changes lie in what range? (c). What is the 30th percentile of the changes in
heart rate?.
Resting heart rate was measured for a group of subjects and .pdf
1. Resting heart rate was measured for a group of subjects and then the subjects drank 250ml of
coffee. Ten minutes later their heart rates were measured again. The change in heart rate followed
a Normal distribution with a mean increase of 7.3 beats per minute and a standard deviation of
11.1. (a). A negative value for change in heart rate implies that the persons heart rate went down.
What proportion of people had heart rates that went down? (Hint: a heart rate change < 0)? (b).
99% of heart rate changes lie in what range? (c). What is the 30th percentile of the changes in
heart rate?
