Algebra question.

Question

The half-life of carbon-14 is 5600 years. If a piece of charcoal made from the wood of a tree shows only 73% of the carbon-14 expected in living matter, when did the tree die?
The tree died about ______ years ago?
(Do not round until the final answer. Then round to the nearest whole number.)

Answer 1

0.73a₀ = a₀(0.5)^t/5600

0.73 = 0.5^t/5600

ln 0.73 = (t/5600) ln 0.5

 

Can you calculate t and answer?