Question

Bài 4: Tính nhanh 

(4242×12×15) / (2121×15×20)

 

 

Answer 1

=2*4/5*3/4=2*3/5=6/5

Answer 2

`(4242×12×15)/(2121×15×20)`

`= (2xx2121×12×15)/(2121×15×20)`

`=(2×12)/20`

`= 24/20 = 6/5`

 

Answer 3

\(\dfrac{4242\times12\times15}{2121\times15\times20}=\dfrac{2121\times2\times4\times3\times15}{2121\times15\times4\times5}\\ =\dfrac{2\times3}{5}=\dfrac{6}{5}\)

Answer 4

\(\dfrac{\left(4242\times12\times15\right)}{\left(2121\times15\times20\right)}=\dfrac{2\times3\times1}{1\times1\times5}=\dfrac{6}{5}\)