To calculate Ariana's heart rate based on her measurement, you can use the following formula:
\[ \text{Heart Rate (bpm)} = \left( \frac{\text{Number of beats in a given time}}{\text{Duration in seconds}} \right) \times 60 \]
In this case, she counted 15 beats in 10 seconds. Plugging in the values:
\[ \text{Heart Rate (bpm)} = \left( \frac{15 \text{ beats}}{10 \text{ seconds}} \right) \times 60 \]
Calculating that gives:
\[ \text{Heart Rate (bpm)} = 1.5 \text{ beats/second} \times 60 = 90 \text{ bpm} \]
Therefore, Ariana’s current heart rate based on this measurement is 90 bpm.