How do you write $-0.875$ as a fraction?

Hint: In the given question, we have been asked to convert a decimal number into a fraction. To convert to a fraction we simply have to remove the decimal points by multiplying with powers of $10$.

Complete step by step solution:
First of all, we should know what a decimal is, a decimal is simply a representation of a system of numbers based on the number ten, tenth parts, and powers of ten. We will convert the given fraction into another equivalent fraction with a denominator of power 10.
The given decimal number is $-0.875$.
Now, to convert the decimal into a fraction we will multiply it by $1000$ on the numerator and denominator.
\[-0.875=-0.875\times \dfrac{1000}{1000}\]
\[=-\dfrac{875}{1000}\]
reduce the fraction by dividing both numerator and denominator by GCF $=125$,
 \[=-\dfrac{875\div 125}{1000\div 125}\]
Therefore,
\[=-\dfrac{7}{8}\]

Hence, \[-\dfrac{7}{8}\] is the required answer.

Note:
So, for solving questions of such type, we first write what has been given to us, and then we simply get the fraction by trying to remove the decimal points from it. A decimal is simply a representation of a system of numbers based on the number ten, tenth parts, and powers of ten.