【题目】下面各题,能简便计算的用简便方法计算。
48×0.99 0.25×3.2×12.5 ×23-2÷ ×[÷(-)]
【答案】47.52;10;15;4
【解析】
48×0.99,把0.99写成1-0.01,根据乘法分配律简算;
0.25×3.2×12.5,根据乘法结合律简算;
×23-2÷,根据乘法分配律简算;
×[÷(-)],根据四则混合运算顺序解答。
48×0.99
=48×(1-0.01)
=48×1-48×0.01
=48-0.48
=47.52
0.25×3.2×12.5
=0.25×(0.4×8)×12.5
=(0.25×0.4)×(8×12.5)
=0.1×100
=10
×23-2÷
=×23-2×
=×(23-2)
=×21
=15
×[÷(-)]
=×[÷]
=×
=4



