12,48:0,5 x 6,25 x 4 x 2
= 12,48 x 2 x 6,25 x 4 x2
= 12,48 x (2 x 2) x (4x 6,25)
= 12,48 x 4 x 25
= 12,48 x (4x25) = 12,48 x 100 = 1248
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2 x 3,12 x 1,25 : 0,25 x 10
= 2 x 3,12 x 1,25 x 4 x10
= 3,12 x (1,25 x 2) x (4 x 10) = 3,12 x 2,5 x 40 = 3,12 x(2,5 x 40) =3,12 x 100 = 312
Vậy $\frac{12,48:0,5 . 6,25 . 4 . 2 }{2 . 3,12 . 1,25 : 0,25 . 10}$ = $\frac{1248}{312}$ = 4
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