A) 6.25%
B) 93.75%
C) 12.5%
D) 87.5%
Correct Answer: A
Solution :
\[T=n\times {{t}_{1/2}}\] \[20=n\times 5\] \[n=4\] \[\frac{N}{{{N}_{0}}}={{\left( \frac{1}{2} \right)}^{n}}\] \[\frac{N}{100}={{\left( \frac{1}{2} \right)}^{4}}\]or \[N=\frac{100}{16}=6.25%\]You need to login to perform this action.
You will be redirected in
3 sec