On a regular ECG running at 25 mm/s, the R–R interval is 10 large squares. What is the heart rate?
Answer and explanation
Correct answer: C. 30 beats/min
- Step 1: Heart rate .
- Step 2: beats/min.
Answer
30 beats/min.
Why not the others: 600 beats/min: The number of squares was multiplied by 60. 150 beats/min: Small squares (1500) were used with large squares. 15 beats/min: 300 was halved.
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