Question

[Tùng]

 

Answer 1

[Nguyễn Lê Phước Thịnh]

a: \(A=\dfrac{1}{2}:\dfrac{1}{20}-\dfrac{3}{5}\)

\(=\dfrac{1}{2}\cdot\dfrac{20}{1}-\dfrac{3}{5}\)

\(=10-\dfrac{3}{5}=\dfrac{47}{5}\)

b: \(B=1,2+2,5\cdot2-4,8\)

\(=1,2+5-4,8\)

=5-3,6=1,4

c: \(C=\dfrac{3}{13}\cdot\dfrac{9}{4}+\dfrac{3}{4}\cdot\dfrac{4}{-13}-\dfrac{3}{13}\cdot\dfrac{1}{4}+\dfrac{10}{13}\)

\(=\dfrac{3}{13}\left(\dfrac{9}{4}-\dfrac{4}{4}-\dfrac{1}{4}\right)+\dfrac{10}{13}\)

\(=\dfrac{3}{13}\cdot\dfrac{4}{4}+\dfrac{10}{13}=\dfrac{3}{13}+\dfrac{10}{13}=1\)

d: \(D=\left(3\dfrac{1}{3}+5\dfrac{2}{3}\right)\cdot\left(-2014^{12}\right)^0-30\%\cdot2,5\)

\(=\left(3+\dfrac{1}{3}+5+\dfrac{2}{3}\right)-0,3\cdot2,5\)

\(=9-0,75=8,25\)