Use the image to answer the question.
A graph shows an x-axis representing time in seconds ranging from 0 to 12 in increments of 2. The y-axis represents heartbeats ranging from 0 to 18 in increments of 3. The graph shows a line representing resting heart rate. The line passes through the following plotted points: left parenthesis 4 comma 6 right parenthesis; left parenthesis 6 comma 9 right parenthesis; left parenthesis 10 comma 15 right parenthesis; and left parenthesis 12 comma 18 right parenthesis.
What is the average number of heartbeats per second?
(1 point)
Responses
2 beats per second
2 beats per second
23 beat per second
Start Fraction 2 over 3 End Fraction beat per second
112 beats per second
1 Start Fraction 1 over 2 End Fraction beats per second
3 beats per second
3 beats per second
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The average number of heartbeats per second can be found by dividing the total number of heartbeats by the total time.
From the graph, we can see that the total number of heartbeats is 18 and the total time is 12 seconds.
Therefore, the average number of heartbeats per second is 18 divided by 12, which is 3 beats per second.
To find the average number of heartbeats per second, we need to calculate the slope of the line representing the resting heart rate on the graph.
The line passes through the points (4, 6), (6, 9), (10, 15), and (12, 18).
To calculate the slope, we use the formula:
slope = (change in y) / (change in x)
First, we calculate the change in y and change in x for two points:
- For the points (4, 6) and (6, 9), change in y = 9 - 6 = 3 and change in x = 6 - 4 = 2.
- For the points (10, 15) and (12, 18), change in y = 18 - 15 = 3 and change in x = 12 - 10 = 2.
Now, we calculate the average slope using the two calculations:
- Average slope = (3 + 3) / (2 + 2) = 6 / 4 = 1.5.
Since the x-axis represents time in seconds, the average number of heartbeats per second is equal to the slope. So the answer is 1.5 beats per second.
To find the average number of heartbeats per second, we need to divide the total number of heartbeats by the total time in seconds.
From the graph, we can see that the heart rate starts at 6 beats at 4 seconds, then increases to 9 beats at 6 seconds, further increases to 15 beats at 10 seconds, and finally reaches 18 beats at 12 seconds.
Therefore, the total number of heartbeats is 6 + 9 + 15 + 18 = 48 beats.
The total time interval is from 0 to 12 seconds, which is 12 seconds.
To find the average number of heartbeats per second, we divide the total number of heartbeats by the total time:
Average heart rate = Total heartbeats / Total time
Average heart rate = 48 beats / 12 seconds
Average heart rate = 4 beats per second
So, the average number of heartbeats per second is 4 beats per second.