\(\dfrac{6}{21}-\dfrac{-12}{44}+\dfrac{10}{12}-\dfrac{-1}{4}-\dfrac{18}{33}\)
\(=\dfrac{6}{21}+\dfrac{12}{44}+\dfrac{10}{12}+\dfrac{1}{4}-\dfrac{18}{33}\)
\(=\dfrac{1013}{924}\)
\(\dfrac{6}{21}-\dfrac{-12}{44}+\dfrac{10}{44}-\dfrac{1}{-4}-\dfrac{18}{33}\)
\(=\dfrac{2}{7}+\dfrac{3}{11}+\dfrac{5}{7}+\dfrac{1}{4}-\dfrac{9}{11}\)
\(=\left(\dfrac{2}{7}+\dfrac{5}{7}\right)+\left(\dfrac{3}{11}-\dfrac{9}{11}\right)+\dfrac{1}{4}\)
\(=1+-\dfrac{6}{11}+\dfrac{1}{4}\)
\(=\dfrac{5}{11}+\dfrac{1}{4}\)
\(=\dfrac{31}{44}\)