Question

Please Help Me! It’s Math! Please!

Answer 1

Answer:

D. About 800 years

Step-by-step explanation:

Use the half-life equation:

A = A₀ (½)ⁿ

where A is the final amount,

A₀ is the initial amount,

and n is the number of half-lives.

0.90A₀ = A₀ (½)ⁿ

0.90 = (½)ⁿ

To solve for n, take log of both sides:

log 0.9 = n log 0.5

n = (log 0.9) / (log 0.5)

n = 0.152

It takes 0.152 half-lives.  The half-life of carbon-14 is 5730 years.

0.152 × 5730 years = 871 years

The closest answer is D.