#### Answer

$\frac{1}{10t}$

#### Work Step by Step

We rewrite the given ratio as a fraction: $\frac{0.72t}{7.2t^2}$
Next, we find a common factor that is in both the numerator and the denominator, and factor it out: $\frac{0.72t}{0.72t(10t)}$
When you divide any number by itself, you get $1$. Therefore, we can cancel out the common factor. This leaves us with $\frac{1}{10t}$.