The half-life of carbon-14 is 5,730 years. Assuming you start with 100% of carbon-14, what is the expression for the percent, P(t), of carbon-14 that remains in an organism that is t years old and what is the percent of carbon-14 remaining (rounded to the nearest whole percent) in an organism estimated to be 30,000 years old?
P(t) = 100(0.5)t/5,730, 3% remaining
P(t) = 100(0.5) 5,730t, 19% remaining
P(t) = 5,730(0.5)^100/t 5,717 remaining
P(t) = 100(0.5)^5,730/t, 97% remaining

Question

The half-life of carbon-14 is 5,730 years. Assuming you start with 100% of carbon-14, what is the expression for the percent, P(t), of carbon-14 that remains in an organism that is t years old and what is the percent of carbon-14 remaining (rounded to the nearest whole percent) in an organism estimated to be 30,000 years old? 
P(t) = 100(0.5)t/5,730, 3% remaining
P(t) = 100(0.5) 5,730t, 19% remaining
P(t) = 5,730(0.5)^100/t 5,717 remaining
P(t) = 100(0.5)^5,730/t, 97% remaining