\(=\dfrac{1}{10}+\dfrac{1}{12}+\dfrac{1}{15}=\dfrac{6}{60}+\dfrac{5}{60}+\dfrac{4}{60}=\dfrac{15}{60}=\dfrac{1}{4}\)
\(=\dfrac{1.6}{10.6}-\dfrac{\left(-1\right).5}{12.5}+\dfrac{1.4}{15.4}=\dfrac{6}{60}+\dfrac{-5}{60}+\dfrac{4}{60}=\dfrac{5}{60}=\dfrac{1}{12}\)