Đáp án + Giải thích các bước giải:

$Bài$ $2$ $:$ $Tính$ $hợp$ $lý$ $( Nếu có thể )$

$A$ $=$ $273$ $\times$ $2018$ $-$ $273$ $\times$ $1000$ $-$ $18$ $\times$ $273$

$A$ $=$ $273$ $\times$ $( 2018 - 1000 - 18 )$

$A$ $=$ $273$ $\times$ $1000$

$A$ $=$ $273 000$

$______________________________________$

$B$ $=$ $6024$ x $324$ + $354$ x $3012$

$B$ $=$ $3012$ x $2$ x $324$ + $354$ x $3012$

$B$ $=$ $3012$ x $( 648 + 354 )$

$B$ $=$ $3012$ x $1002$

$B$ $=$ $3 018 024$

$__________________________________________$

$C$ $=$ $84$ $\times$ $15$ $-$ $28$ $\times$ $45$ $+$ $1000$

$C$ $=$ $84$ $\times$ $15$ $-$ $28$ $\times$ $15$ $\times$ $3$ $+$ $1000$

$C$ $=$ $15$ $\times$ $( 84 - 84 )$ $+$ $1000$

$C$ $=$ $15$ $\times$ $0$ $+$ $1000$

$C$ $=$ $0$ $+$ $1000$

$C$ $=$ $1000$

@namlebao

    Chúc cậu học giỏi nha, PLS câu trả lời hay nhất.

`A=273 xx 2018 - 273 xx 1000 - 18 xx 273`

`A=273 xx (2018 - 1000 - 18)`

`A=273 xx 1000`

`A=27300`

Vậy `A=27300`

`B=6024 xx 324 + 354 xx 3012`

`B=3012 xx 2 xx 324 + 354 xx 3012`

`B=3012 xx 648 + 354 xx 3012`

`B=3012xx (648 + 354)`

`B=3012 xx 1002`

`B=3018024`

Vậy `B=3018024`

`C=84 xx 15 - 28 xx 45 + 1000`

`C=84 xx 15 - 28 xx 15 xx 3 +1000`

`C=84 xx 15 - 84 xx 15 + 1000`

`C=84 xx (15-15) + 1000`

`C=84 xx 0 +1000`

`C=0+1000`

`C=1000`

Vậy `C=1000`