计算:(1)1.25×1.25×┄×1.25×0.8×0.8×┄×0.812个1.25 13个0.8(2)31.6×7.6+184×0.77(3)(6+43+473+5414+43444) ×2.5应该是有一种适合孩子的简单算法吧?
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/06 14:13:30
![计算:(1)1.25×1.25×┄×1.25×0.8×0.8×┄×0.812个1.25 13个0.8(2)31.6×7.6+184×0.77(3)(6+43+473+5414+43444) ×2.5应该是有一种适合孩子的简单算法吧?](/uploads/image/z/8938103-23-3.jpg?t=%E8%AE%A1%E7%AE%97%3A%EF%BC%881%EF%BC%891.25%C3%971.25%C3%97%E2%94%84%C3%971.25%C3%970.8%C3%970.8%C3%97%E2%94%84%C3%970.812%E4%B8%AA1.25+13%E4%B8%AA0.8%EF%BC%882%EF%BC%8931.6%C3%977.6%2B184%C3%970.77%EF%BC%883%EF%BC%89%286%2B43%2B473%2B5414%2B43444%29+%C3%972.5%E5%BA%94%E8%AF%A5%E6%98%AF%E6%9C%89%E4%B8%80%E7%A7%8D%E9%80%82%E5%90%88%E5%AD%A9%E5%AD%90%E7%9A%84%E7%AE%80%E5%8D%95%E7%AE%97%E6%B3%95%E5%90%A7%3F)
计算:(1)1.25×1.25×┄×1.25×0.8×0.8×┄×0.812个1.25 13个0.8(2)31.6×7.6+184×0.77(3)(6+43+473+5414+43444) ×2.5应该是有一种适合孩子的简单算法吧?
计算:
(1)1.25×1.25×┄×1.25×0.8×0.8×┄×0.8
12个1.25 13个0.8
(2)31.6×7.6+184×0.77
(3)(6+43+473+5414+43444) ×2.5
应该是有一种适合孩子的简单算法吧?
计算:(1)1.25×1.25×┄×1.25×0.8×0.8×┄×0.812个1.25 13个0.8(2)31.6×7.6+184×0.77(3)(6+43+473+5414+43444) ×2.5应该是有一种适合孩子的简单算法吧?
是的,有简便算法.
(1)1.25×1.25×┄×1.25×0.8×0.8×┄×0.8
= (1.25×0.8)×┄×(1.25×0.8)×0.8
12个(1.25×0.8) 1个0.8
= 1×┄×1×0.8
=0.8
(2)31.6×7.6+184×0.77
= 316×0.76 + 184×(0.76+0.01)
= (316+184)×0.76 + 184×0.01
= 500×0.76 + 1.84
= 380 + 1.84
= 381.84
(3)(6+43+473+5414+43444) ×2.5
= [(6+5414)+(43+473)+43444]×2.5
= (5420+516+43444)×2.5
= (5420/4+516/4+43444/4)×4×2.5
= (1355+129+10861)×10
= 123450
最后这题我没有想到特别简便的方法,基本上是硬算了.