A regular resting pulse is counted as 21 beats over 15 seconds. Convert to beats per minute using count × 60 / counting seconds.
- A84 bpm
- B126 bpm
- C63 bpm
- D42 bpm
Show answer and explanations
Answer
A
21 × (60/15) = 84 bpm. A short count has measurement error.
B
21 × 6 = 126: a factor of 6 is for a 10-second count, but this count lasted 15 seconds.
C
21 × 3 = 63: a factor of 3 is for a 20-second count, but this count lasted 15 seconds.
D
21 × 2 = 42: a factor of 2 is for a 30-second count, but this count lasted 15 seconds.
A
21 × (60/15) = 84 bpm. A short count has measurement error.