To divide two fractions, you can multiply the first fraction by the reciprocal of the second fraction.
The problem is:
\[ -\frac{5}{12} \div -\frac{15}{16} \]
This can be rewritten as:
\[ -\frac{5}{12} \times -\frac{16}{15} \]
Since multiplying two negative fractions gives a positive result, we can remove the negatives:
\[ \frac{5}{12} \times \frac{16}{15} \]
Next, multiply the numerators and the denominators:
\[ \frac{5 \times 16}{12 \times 15} = \frac{80}{180} \]
Now, we simplify \(\frac{80}{180}\). First, find the greatest common divisor (GCD) of 80 and 180. The GCD is 20.
Now, divide both the numerator and the denominator by their GCD:
\[ \frac{80 \div 20}{180 \div 20} = \frac{4}{9} \]
So, the answer is:
\[ \frac{4}{9} \]