A doctor observes a graph that shows the electrical activity (in volts) of the heart of a patient over a period of time (in seco
nds). Each local maximum of 0.004 volts corresponds to one heartbeat. The doctor needs to calculate the heart rate of the patient in beats per minute. What is the heart rate of this patient? ____ beats per minute
By looking at the graph, we see that exactly at second 6, the 9th beat occurs. We can take that to beats/min by multiplying that relation by 10 (since there are ten 6sec in one minute).