Question

Tính nhanh: (-28) . 67 + (-28) . 33 + 400
 

Answer 1

(-28) .67 + (-28).33 + 400

= -28.( 67 + 33) + 400

= -28 . 100 + 400

= - 2800 + 400

= -2400

Answer 2

\(\left(-28\right)\cdot67+\left(-28\right)\cdot33+400\)

\(=\left(-28\right)\cdot\left(67+33\right)+400\)

\(=\left(-28\right)\cdot100+400\)

\(=-2800+400=-2400\)