Question

Tính nhanh: 

\(\dfrac{9}{8}x\dfrac{8}{7}x\dfrac{7}{3}x\dfrac{1}{3}\)

Answer 1

\(=\dfrac{9}{7}\cdot\dfrac{7}{9}=1\)

Answer 2

\(\dfrac{9}{8}x\dfrac{8}{7}x\dfrac{7}{3}x\dfrac{1}{3}=\dfrac{9x8x7x1}{8x7x3x3}=1\)

Answer 3

\(=\dfrac{9x8}{8x7}x\)\(\dfrac{7}{3.3}\) 
= \(\dfrac{9}{7}.\)\(\dfrac{7}{9}=1\)