用递等式计算.25×4﹣240÷4 [300﹣(56+44)]÷25 (72÷8+21)×3.
用简便方法计算.13.6﹣4.25﹣5.75 45×99+45 45+99+156 125×32×25.
158+97+42.
简便计算①2.8×0.5+0.5×27.2 ②3.56+6.1+6.44 ③17.67﹣2.77﹣2.23 ④11÷2.5÷0.4.
7.08×1.3+8.7×7.08.
怎样算简便就怎样算.; 4﹣﹣; ×58+42÷8;36×(+﹣); (15﹣14×)×; ÷﹣÷.