#### Answer

$\frac{1}{3}$

#### Work Step by Step

30 minutes to 90 minutes
$\frac{30 minutes}{90 minutes}$
now as both numerator and denominator has same unit it can be divided out.
$\frac{30}{90}$
Now divide both numerator and denominator by 30.
$\frac{30 ÷30 }{90 ÷30}$
it can be written as a fraction in the lowest term as $\frac{1}{3}$