Question

tính nhanh: 7,89 x 105 - 7,89 x 3 - 7,89 - 7,89

Answer 1

=7,89(105-103-1-1)=7,89x100=789

Answer 2

\(7,89\times105-7,89\times3-7,89-7,89\\ =7,89\times\left(105-3-1-1\right)\\ =7,89\times100\\ =789\)

Answer 3

=789

Answer 4

cảm hơn các bn nhiều nha

Answer 5

= 7,89 x (105 - 3 - 1 - 1)

= 7,89 x 100

=> 789