Question

9/11-20/55=?

Answer 1

\(\dfrac{9}{11}-\dfrac{20}{55}=\dfrac{45}{55}-\dfrac{20}{55}=\dfrac{25}{55}=\dfrac{5}{11}\)

cũng có thể rút gọn 20/55=4/11 và tính tiếp

Answer 2

25/55=5/11

Answer 3

Cách 1: Ta có:

\(\dfrac{9}{11}\) - \(\dfrac{20}{55}\) = \(\dfrac{9\cdot5}{11\cdot5}\) - \(\dfrac{20}{55}\) = \(\dfrac{45}{55}\) - \(\dfrac{20}{55}\) = \(\dfrac{25}{55}\) = \(\dfrac{5}{11}\)

Cách 2: Ta có:

\(\dfrac{9}{11}\) - \(\dfrac{20}{55}\) = \(\dfrac{9}{11}\) - \(\dfrac{20:5}{55:5}\) = \(\dfrac{9}{11}\) - \(\dfrac{4}{11}\) = \(\dfrac{5}{11}\)

Tick cho chị e nhé :))))))))