Bài 1: Tính Nhẩm a, 9.24.25 b, 12.125.54 c, 64.125.54 d, 425.7.4-170.60 e, 8.9.14+6.17.12+19.4.18 help me

Đáp án`+`Giải thích các bước giải:

`9.24.25`

`= 9.6.4.25`

`= 54.100`

`= 5400`

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`12.125.54`

`= 3.4.125.2.27`

`= 1000.3.27`

`= 1000.81`

`= 81000`

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`64.125.54`

`= 8.8.125.54`

`= 1000.8.54`

`= 1000.432`

`= 432000`

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`425.7.4-170.60`

`=(425.4).7-170.6.10`

`=1700.7-170.10.6`

`=1700.7-1700.6`

`=1700.(7-6)`

`=1700`

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`8.9.14+6.17.12+19.4.18`

`= 2.4.9.14+2.3.17.4.3+2.4.9.19`

`=2.4.9.( 14+17+19)`

`= 72.50`

`= 3600`