Question

19✘0.39+0.37✘38用简便方法？

Answer 1

原式=19x0.39+19x2x0.37
=19（0.39+0.74）
=19x1.13
=20x1.13-1.13
=22.6-1.13
=21.47

Answer 2

19✘0.39+0.37✘38
=19x0.39+0.37x19x2
=19x(0.39+0.37x2)
=19x(0.39+0.74)
=19x(1.13)
=19+19x0.13
=19+2.47
=21.47

Answer 3

19×0.39+0.37×38
=19×0.39+0.37×2×19
=19×0.39+0.74×19
=19×(0.39+0.74)
=19×1.13
=(20-1)×1.13
=20×1.13-1×1.13
=22.6-1.13
=21.47

Answer 4

巧算19×0.39+0.37×38
解题思路:四则运算规则(按顺序计算,先算乘除后算加减,有括号先算括号,有乘方先算乘方)即脱式运算(递等式计算)需在该原则前提下进行

解题过程:
19×0.39+0.37×38

=19×(0.39+0.37×2)

=19×1.13

=21.47

扩展资料→计算结果:先将两乘数末位对齐,然后分别使用第二个乘数,由末位起对每一位数依次乘上一个乘数,最后将所计算结果累加即为乘积,如果乘数为小数可先将其扩大相应的倍数,最后乘积在缩小相应的倍数；

解题过程:
步骤一:3×19=57

步骤二:1×19=190

步骤三:1×19=1900

根据以上计算步骤组合结果向左移动2位小数点积为21.47

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