Answer:
t = 6.3
Explanation:
N=Noe^(-kt)
No = 14 grams
k = .1092
We want to find t when N = 7 or 1/2 of 14
N=Noe^(-kt)
7 = 14 e ^ (-.1092t)
Divide each side by 14
1/2 = e ^ (-.1092t)
take the natural log of each side
ln (1/2) = ln e ^ (-.1092t)
ln (1/2) = -.1092t
Divide each side by -.1092
ln (1/2)/ -.1092 = t
tâ6.3475
Rounding to the nearest tenth
t = 6.3