2.5×7×9.6×12.5这么巧算
问题描述:
2.5×7×9.6×12.5这么巧算
答
2.5×7×9.6×12.5
=2.5×7×(4×2.4)×12.5
=2.5×4×7×(2.4×12.5)
=70×(3×0.8×12.5)
=70×30
=2100