Question

Tính nhanh

\(4\dfrac{8}{15}-5\dfrac{7}{12}-0\dfrac{1}{15}\)

Tính

\(\dfrac{-3}{5}-\dfrac{4}{5}\cdot\dfrac{10}{3}\)

Answer 1

4\(\dfrac{8}{15}\)- 5 \(\dfrac{7}{12}- \dfrac{1}{15}\) (vì 0\(\dfrac{1}{15}=\dfrac{1}{15}\) )

= (4-0) + ( \(\dfrac{8}{15}-\dfrac{1}{15}\)) -5\(\dfrac{7}{12}\)

= 4 + \(\dfrac{7}{15}\) -5 \(\dfrac{7}{12}\)

= 4\(\dfrac{7}{15}\) - 5\(\dfrac{7}{12}\)

= (4-5) + ( \(\dfrac{7}{15}\) - \(\dfrac{7}{12}\) )

= (-1) + (\(\dfrac{28}{60}-\dfrac{35}{60}\) )

= -1 + \(\dfrac{-7}{60}\)

= -1\(\dfrac{7}{60}\)

tính

\(\dfrac{-3}{5}-\dfrac{4}{5}.\dfrac{10}{3}\)

= \(\dfrac{-3}{5}\) - \(\dfrac{40}{15}\)

= \(\dfrac{-9}{15}\) - \(\dfrac{40}{15}\)

= \(\dfrac{-49}{15}\)