Question

Cobalt (6027Co) has a half life of 30 years. If you begin with 27 kg of cobalt, how much will remain after 11 years?

a.) 16 kg
b.) 15 kg
c.) 17 kg
d.) 21 kg
e.) 19 kg

Answer 1

Equation editor isn't working for me today, sorry.

N(t) = N(0) (1/2)^(t/th)

Find N(t):
N(0) = 27 kg
t = 11 a
th = 30 a

N(t) = 27 kg x (0.5)^(11/30)
and solve for N(t)