Question

Tính bằng cách hợp lí:

a)   (9/25 - 2 . 18 ) / (19/5 + 0,2 )

b)    12 . (-2/3)^2 + 4/3

Answer 1

a) \(=\frac{\left(\frac{9}{25}-36\right)}{\frac{19}{5}+\frac{1}{5}}=\frac{\frac{9}{25}-\frac{900}{25}}{\frac{20}{5}}=\frac{-891}{25}:4\)\(=\frac{-891}{25\cdot4}=\frac{-891}{100}=-8,91\)

b) \(=12\cdot\frac{\left(-2\right)^2}{3^2}+\frac{4}{3}=12\cdot\frac{4}{9}+\frac{4}{3}\)\(=\frac{48}{9}+\frac{4}{3}=\frac{48}{9}+\frac{12}{9}=\frac{60}{9}\)

Answer 2

(9/25-2.18) : (19/5+0,2) mà bạn