Question

Tính nhanh bằng 2 cách:

15 x 6 + 20 x3 + 25 x 14 =

Answer 1

15x6+20x3+25x14

=90+60+350

=500

15x6+20x3+25x14

=5x3x6+5x4x3+5x5x14

=5x(3x6+4x3+5x14)

=5x100

=500

Answer 2

C1 :

15 x 6 + 20 x 3 + 25 x 14 

= 90 + 60 + 350

= 500

C2 :

15 x 6 + 20 x 3 + 25 x 14

= 5 x 3 x 6 + 5 x 4 x 3 + 5 x 5 x 14

= 5 x 18 + 5 x 12 + 5 x 70

= 5 x 100

= 500