Question

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tinh nhanh

a, 21 x 45 

9 x 7 x 5 x3

b,3 x 6 x 9 x 12

4 x 8 x 18 x 27

mong mn giup do

Answer 1

[linh ngọc]

a,21x45=945

9x7x5x3=945

b,3x6x9x12x=1944

4x8x18x27=15552