Question

tính bằng cách thuận tiện:

a) 27 x 38 + 62 x 27 - 27 x 90

Answer 1

`#040911`

`a)`

`27 \times 38 + 62 \times 27 - 27 \times 90`

`= 27 \times (38 + 62 - 90)`

`= 27 \times (100 - 90)`

`= 27 \times 10`

`= 270`

Answer 2

\(27\times38+62\times27-27\times90\)

\(=27\times\left(38+62-90\right)\)

\(=27\times\left(100-90\right)\)

\(=27\times10\)

\(=270\)