Question

Tính bằng cách thuận tiện nhất

A)1/4 + 2/5 + 3/4 + 3/5

Answer 1

\(\dfrac{1}{4}+\dfrac{2}{5}+\dfrac{3}{4}+\dfrac{3}{5}\)
\(=\left(\dfrac{1}{4}+\dfrac{3}{4}\right)+\left(\dfrac{2}{5}+\dfrac{3}{5}\right)\)
\(=1+1\)
\(=2\)

#Sahara

Answer 2

`1/4+2/5+3/4+3/5`

`=(1/4+3/4)+(2/5+3/5)`

`=4/4+5/5`

`=1+1`

`=2`

Answer 3

= ( 1/4 + 3/4 ) + ( 2/5 + 3/5 ) 

= 1 + 1

= 2