To solve \(-123.45 - (-234.76)\), we can use the property of the additive inverse. Subtracting a negative number is the same as adding its positive counterpart.
Therefore:
\[ -123.45 - (-234.76) = -123.45 + 234.76 \]
Now, we can perform the addition:
\[ -123.45 + 234.76 = 234.76 - 123.45 \]
Calculating the difference:
\[ 234.76 - 123.45 = 111.31 \]
Thus, the answer is:
\[ \boxed{111.31} \]