Question

Tính nhanh: 30x10+30x20+30x30+30x40=?

Answer 1

30x(10+20+30+40)

=30x100

=3000

nha bn

Answer 2

= 3000

Answer 3

30.10+30.20+30.30+30.40

=30.(10+20+30+40)

=30.      100

=      3000

Answer 4

30 x 10 + 30 x 20 + 30 x 30 + 30 x 40 

= 30 x ( 10 + 20 + 30 + 40 )

= 30 x 100

= 3000

k mk nha !!!!!!!!

Answer 5

= 300

k minh nha