# earth science

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if carbon 14 has a half life of 24 days how much would be left of 220 gram sample after 168 days

• earth science -

the amount left after t days is

220 (1/2)^(t/24)

so,

220(1/2)^(168/24) = 1.718g

168 days is 7 half-lives, so 1/128 remains.

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