Sos cứuuuuuuuuuuuuuuu

Đáp án + giải thích các bước giải:

`184 + 192 + 11 + 166 + 47`

`= (184 + 166) + (47 + 11 + 192)`

`= 350 + 250`

`= 600`

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`241 + 124 + 175 + 27 + 134 + 69`

`= (241 + 69) + (124 + 134) + (175 + 27)`

`= 310 + 258 + 202`

`= 310 + 460`

`= 770`

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`69 + 27 + 123 + 308 + 23`

`= (27 + 23)+(123 + 308 + 69)`

`= 50 + 431 + 69`

`= 50 + 500`

`= 550`

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`389 + 132 - 89 - 32`

`= (389 - 89) + (132 - 32)`

`= 300 + 100`

`= 400`

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`267 - 32 + 148 - 35 - 48`

`= (267 - 32 - 35)+ (148 - 48)`

`= 200 + 100`

`= 300`

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`321 - 46 + 127 - 27 + 25`

`= (321 - 46 + 25) + (127 - 27)`

`= 300 + 100`

`= 400`

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`1234 - 432 + 345 - 54 -102-91`

`= (1234 - 54) + (345 - 432 - 102 - 91)`

`= 1180 - 280`

`=  900` 

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`1001 - 89 + 1010 - 12 - 110`

`= (1001 + 1010) + (-89 - 12 - 110)`

`= 1011 - 211`

`= 800`

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`10 + 11 + 12 + ... 20`

Số số hạng: `(20 - 10) :1 + 1 = 11` số 

Tổng: `(20 + 10)xx 11 :2 = 165`

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`15 + 16 + 17 + .... + 35`

Số số hạng: `(35 - 15) : 1 + 1 = 21` số

Tổng: `(35 + 15) xx 21 : 2 = 525`