a)
\(\dfrac{-4}{12}+\dfrac{14}{21}\)
\(=\dfrac{-84}{252}+\dfrac{168}{252}\)
\(=\dfrac{1}{3}\)
b)
\(\dfrac{-8}{3}.\dfrac{2}{11}-\dfrac{8}{3}:\dfrac{11}{9}\)
\(=\dfrac{-8}{3}.\dfrac{2}{11}-\dfrac{3}{8}.\dfrac{9}{11}\)
\(=\dfrac{-16}{33}-\dfrac{3}{8}.\dfrac{9}{11}\)
\(=\dfrac{-16}{33}-\dfrac{27}{88}\)
\(=\dfrac{-1408}{2904}-\dfrac{891}{2904}\)
\(=\dfrac{-19}{24}\)
c)
\(0,1.\sqrt{400}+0,2.\sqrt{1600}\)
\(=0,1.20+0,2.40\)
\(=2+0,2.40\)
\(=2+8\)
\(=10\)
d)
\(\left(\dfrac{-1}{3}\right)^2-\dfrac{3}{8}:\left(0,5\right)^3-\dfrac{5}{2}.\left(-4\right)+2022^0\)
\(=\dfrac{1}{9}-\dfrac{3}{8}:\dfrac{1}{8}-\dfrac{5}{2}.\left(-4\right)+1\)
\(=\dfrac{1}{9}-\dfrac{3}{8}.\dfrac{8}{1}-\dfrac{5}{2}.\left(-4\right)+1\)
\(=\dfrac{1}{9}-3-\dfrac{5}{2}.\left(-4\right)+1\)
\(=\dfrac{1}{9}-3-\left(-10\right)+1\)
\(=\dfrac{-26}{9}-\left(-10\right)+1\)
\(=\dfrac{64}{9}+1\)
\(=\dfrac{73}{9}\)
