Question

tính ( làm hẳn phép tính )

-2/3.5/7+5/7:3/4-1

Answer 1

\(\dfrac{-2}{3}\cdot\dfrac{5}{7}+\dfrac{5}{7}:\dfrac{3}{4}-1=\dfrac{-2}{3}\cdot\dfrac{5}{7}+\dfrac{5}{7}\cdot\dfrac{4}{3}-1=\left(\dfrac{-2}{3}+\dfrac{4}{3}\right)\cdot\dfrac{5}{7}-1=\dfrac{2}{3}\cdot\dfrac{5}{7}-1=\dfrac{10}{21}-1=-\dfrac{11}{21}\)

Answer 2

−2 / 3⋅5 / 7+5 / 7:3 / 4−1=−2 / 3⋅5 / 7+5 / 7⋅4 / 3−1=(−2 / 3+4 / 3)⋅5 /. 7−1=2 / 3⋅5 / 7−1=10 / 21−1=−11 / 21

nha