If for every 5 units of carbon-14 in a sample there were 15 units of nitrogen-14,the age of the sample would be about
A) 17,190 years.
B) 11,460 years.
C) 5730 years.
D) 2865 years.
E) 1432.5 years.

Question

Quizplus · Accepted Answer

Carbon-14 decays into nitrogen-14 over time, with a half-life of approximately 5730 years. If there are 15 units of nitrogen-14 for every 5 units of carbon-14, this means the original amount of carbon-14 has halved once (since the ratio of carbon-14 to nitrogen-14 is 1:3, indicating two-thirds of the original carbon-14 has decayed). Therefore, the sample is approximately one half-life old, or about 11,460 years.

If for Every 5 Units of Carbon-14 in a Sample