Question

Our hearts beat approximately 70 times per minute. Express in scientific notation how many times the heart beats over a lifetime of 73 years​ (ignore leap​ years). Round the decimal factor in your scientific notation answer to two decimal places.

Answer 1

Answer:

2.69 x $10^{9}$

Step-by-step explanation:

We are given the heart's speed - 70 bpm

We count the number of minutes in 73 years :

• 1 year = 365 days
• 1 day = 24 hours
• 1 hour = 60 minutes
• 73 x 365 x 24 x 60 = 38,368,800 minutes

We multiply the heart's bpm with 73 years worth of minutes

38,368,800 x 70 = 2,685,816,000

Write the number in scientific notation = 2.68581 x $10^{9}$ ≈ 2.69 x $10^{9}$