\(-\frac{1}{4}-\frac{5}{6}-\frac{11}{18}\)
\(=-\frac{9}{36}-\frac{30}{36}-\frac{22}{36}\)
\(=-\frac{39}{36}-\frac{22}{36}\)
\(=-\frac{61}{36}\)
\(\frac{1}{4}+\frac{7}{12}-\frac{6}{13}-\frac{7}{8}\)
\(=\frac{78}{312}+\frac{182}{312}-\frac{144}{312}-\frac{273}{312}\)
\(=\frac{260}{312}-\frac{144}{312}-\frac{273}{312}\)
\(=\frac{116}{312}-\frac{273}{312}\)
\(=-\frac{157}{312}\)