Carbon-14 decay (radiocarbon dating) is used in archaeology to measure

the age of ancient pottery. Carbon-14 has a half-life of 5830 years. How old is a
pot in which 20% of the Carbon-14 has decayed?

1 answer

half-life ----> so I will use 1/2 as the base in my exponential equation
half-life is 5830, so I will use t/5830 as my exponent

amount = (1/2)^(t/5830) = .5^(t/5830)

20% has decayed ---> I have 80% or .8 left

.8 = .5^(t/5830)
take log of both sides and use log rules
(t/5830)log .5 = log .8
t/5830 = log.8/log.5
t = 5830log.8/log.5 = .....
You do the button pushing