Question

A doctor observes a graph that shows the electrical activity (in volts) of the heart of a patient over a period of time (in seconds). 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
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Answer 1

its 60 per min

A graph which shows the electrical activity of the heart as a function of time is called an electrocardiogram. Each spike in the graph represents one heart beat.

To find the heart rate in beats per minute, we need to calculate how many heart beats will occur in 60 seconds.

Let's start counting heart beats after the beat at time t=0 seconds. Looking at the graph, we observe that, 6 additional heart beats occur within the first 6 seconds. To find the number of heart beats in one minute we proceed as follows.

This makes sense: 60 beats per minute is equivalent to 1 beat every second, which is what we see in the graph.

The heart rate of the patient is 60 beats per minute.

Answer 2

90 beats per minute

Explanation:

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).

9beats every 6sec * 10 = 90beats/min