Question

mng giải cả cách làm ra hộ m!

Answer 1

a: \(2,54+6,3\cdot\left(-1.25\right)\)

\(=2.54-7,875\)

=-5,335

b: \(\dfrac{1}{5}\cdot\dfrac{4}{7}+\dfrac{3}{7}\cdot\dfrac{1}{5}-\dfrac{1}{5}\)

\(=\dfrac{1}{5}\left(\dfrac{4}{7}+\dfrac{3}{7}\right)-\dfrac{1}{5}\)

\(=\dfrac{1}{5}-\dfrac{1}{5}=0\)

c: \(\dfrac{-10}{13}+\dfrac{5}{17}-\dfrac{3}{13}+\dfrac{12}{17}-\dfrac{11}{20}\)

\(=\left(-\dfrac{10}{13}-\dfrac{3}{13}\right)+\left(\dfrac{5}{17}+\dfrac{12}{17}\right)-\dfrac{11}{20}\)

\(=-1+1-\dfrac{11}{20}=-\dfrac{11}{20}\)