Tính nhanh 125×17-250×6-125×5 16×420+8×160 36×327+65×327-300-27

Đáp án:

`125 × 17 – 250 × 6 – 125 × 5`

`= 125 × 17 – 125 × 2 × 6 – 125 × 5`

`= 125 × (17 – 2 × 6 – 5)`

`= 125 × (17 – 12 – 5)`

`= 125 × 0`

`= 0`

`16 × 420 + 8 × 160`

`= 8 × 2 × 420 + 8 × 160`

`= 8 × (2 × 420 + 160`

`= 8 × (840 + 160)`

`= 8 × 1000`

`= 8000`

`36 × 327 + 65 × 327 – 300 – 27`

`= 327 × (36 + 65) – 327 `

`= 327 × 101 – 327`

`= 327 × (101 – 1)`

`= 327 × 100`

`= 32700`