PROBLEM:

How many times longer than the mean life of an extremely unstable atomic nucleus is the lifetime of a human? (Hint: The lifetime of an unstable atomic nucleus is on the order of  10^-22 s .)

SOLUTION:

The lifetime of a human is 2×10⁹ s, while the lifetime of an unstable atomic nucleus is 10^-22 s.

Therefore, a human lifetime is much longer by

 \frac{T_h}{T_n}=\frac{2\times 10^9\:\text{sec}}{10^{-22}\:\text{sec}}=2\times 10^{31}\:\text{times}\ \qquad \ \color{DarkOrange} \left( \text{Answer} \right)