a 50-mg sample of cobalt-60 decays to 40mg after 1.6min. determine the half-life of the cobalt-60.
this is as far as i got before getting stuck
M = C
40 = 50
0.8 =
=
then right here i get stuck and can't get the correct answer. can somone tell me what i'm doing wrong?
i'm getting the answer 0.52 mins, when its susposed to be 5 mins