1. (10 points) $3 \frac{3}{4}+5 \frac{5}{6}+7 \frac{7}{8}+9 \frac{9}{10}=$
【Analysis】By observation, this problem can first break down each fraction into the form of "integer and decimal fraction", then add the integers and ten thousand separately, and perform the calculation of the fractional part by finding a common denominator.
$$
\begin{array}{l}
\text { 【Solution】Solution: } 3 \frac{3}{4}+5 \frac{5}{6}+7 \frac{7}{8}+9 \frac{9}{10} \\
=(3+5+7+9)+\left(\frac{3}{4}+\frac{5}{6}+\frac{7}{8}+\frac{9}{10}\right) \\
=24+\left(\frac{90}{120}+\frac{100}{120}+\frac{105}{120}+\frac{108}{120}\right) \\
=24+3 \frac{43}{120} \\
=27 \frac{43}{120} .
\end{array}
$$

Therefore, the answer is: $27 \frac{43}{120}$.