b) \(\dfrac{4}{14}-\dfrac{1}{5}+\dfrac{11}{15}-\dfrac{24}{5}\)
\(=-\dfrac{1}{5}-\dfrac{24}{5}+\dfrac{4}{14}+\dfrac{11}{15}\)
\(=-\left(\dfrac{1}{5}+\dfrac{24}{5}\right)+\dfrac{4}{14}+\dfrac{11}{15}\)
\(=-\left(\dfrac{1+24}{5}\right)+\dfrac{4}{14}+\dfrac{11}{15}\)
\(=-\dfrac{25}{5}+\dfrac{4}{14}+\dfrac{11}{15}\)
\(=-5+\dfrac{4}{14}+\dfrac{11}{15}\)
\(=\dfrac{-70}{14}+\dfrac{4}{14}+\dfrac{11}{15}\)
\(=\dfrac{-70+4}{14}+\dfrac{11}{15}\)
\(=\dfrac{-\left(70-4\right)}{14}+\dfrac{11}{15}\)
\(=\dfrac{-66}{14}+\dfrac{11}{15}\)
\(=\dfrac{-990}{210}+\dfrac{154}{210}\)
\(=\dfrac{-990+154}{210}\)
\(=\dfrac{-\left(990-154\right)}{210}\)
\(=\dfrac{-836}{210}\)
\(=\dfrac{-418}{105}\)
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