Question

[dangvuhoaianh]

bài 1 : tính nhanh

a) 2 x 12 x 43 + 3 x 32 x 8 + 25 x 6 x4

b) 78 x 31 + 78 x 24 + 17 x 78 + 28 x 78

mn giúp mik nha

Answer 1

[Kim Thủy]

a) 2 x 12 x 43 + 3 x 32 x 8 + 25 x 6 x4

=(2 x12) x43+(3 x8) x32+(6 x4) x25

=24 x43+24 x32+ 24 x25

=24 x(43+32+25)

=24 x100

=2400

b) 78 x 31 + 78 x 24 + 17 x 78 + 28 x 78

=78x(31+24+17+28)

=78x100

=7800

Answer 2

[dangvuhoaianh]

thanks bạn nha