Question

Thực hiện phép tính (tính nhanh nếu có thể)

a) \(\dfrac{1}{2}\) + \(\dfrac{-2}{3}\)

b) \(\dfrac{-7}{3}\) . \(\dfrac{15}{9}\) - \(\dfrac{10}{9}\)

c) [(-0,7) : 0,07 + 9] . ( 1,3 . 2,5 + 1,3 . 7,5 )

Answer 1

a)\(=\dfrac{3}{6}-\dfrac{4}{6}=-\dfrac{1}{6}\)

b)\(=-\dfrac{35}{9}-\dfrac{10}{9}=-\dfrac{45}{9}=-5\)

c)\(=\left[-10+9\right].\left[1,3.\left(2,5+7,5\right)\right]=-1.\left[1,3.10\right]=-1.13=-13\)

Answer 2