Lifelong heartbeats

 A

Let’s calculate it step by step 👇

1. 

Average human heart rate

A typical resting heart rate:

≈ 70 beats per minute (bpm)

(Healthy adults range between 60–100 bpm.)

2. 

Minutes in a year

60 \text{ min/hr} × 24 \text{ hr/day} × 365 \text{ days/yr} = 525,600 \text{ min/yr}

3. 

Beats per year

70 \text{ bpm} × 525,600 \text{ min/yr} = 36,792,000 \text{ beats/yr}

4. 

Average lifespan

Let’s use 80 years as a rough global average for humans.

5. 

Total beats in a lifetime

36,792,000 × 80 = 2,943,360,000

✅ ≈ 2.9 billion heartbeats in an average human lifetime

💡 Fun comparisons:

• A mouse (fast heart rate ~600 bpm) lives about 3 years → ~0.9 billion beats total.
• An elephant (slow heart rate ~30 bpm) lives about 70 years → also ~1 billion beats total.

So across many mammals, ~1 billion lifetime heartbeats is a surprisingly common biological constant — humans just exceed it thanks to medicine and lower heart rates.