Question

Tính bằng cách thuận tiện nhất: 

3×15×4+12×19+6×66×2

Answer 1

\(3\cdot15\cdot4+12\cdot19+6\cdot66\cdot2\)

\(=\left(3\cdot4\right)\cdot15+12\cdot19+\left(6\cdot2\right)\cdot66\)

\(=12\cdot15+12\cdot19+12\cdot66\)

\(=12\cdot\left(15+19+66\right)\)

\(=12\cdot100\)

\(=1200\)

Answer 2

\(3.15.4+1.19+6.66.2\)

= ( 3. 4 ) . 15 + 12 .19 - (6.2) . 66

= 12 . 15 + 12 . 19 + 12 . 66

= 12.(15 + 19 + 66)

= 2 . 100

= 1200