Question

Tính nhanh :

a, 12 . 125 . 54

​b, 998 . 34

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Answer 1

a, 12 . 125 . 54

=4*3*25*5*2*27

=(25*4)*(5*2)*(27*3)

=100*81*10

=81*1000

=81000

Answer 2

a, 12 . 125 . 54

= ( 125 . 4 . 2 ) . 3 . 27

= 1000 . 81

= 81000

b, 998 . 34 

= ( 1000 - 2 ) . 34

= 1000 . 34 - 2 . 34

= 34000 - 68

= 33923