问题 解答题

脱式计算(用你自己喜欢的方法)

①1.12+1.79+8.88+0.21

②73.2-16.3-3.7

③99×3.6+3.6

④7.9×0.8×0.125

⑤4×8.8×0.25

⑥0.36×101.

答案

(1)1.12+1.79+8.88+0.21,

=(1.12+8.88)+(1.79+0.21),

=10+2,

=12;

(2)73.2-16.3-3.7

=73.2-(16.3+3.7),

=73.2-20,

=53.2;

(3)99×3.6+3.6,

=(99+1)×3.6,

=100×3.6,

=360;

(4)7.9×0.8×0.125

=7.9×(0.8×0.125),

=7.9×0.1,

=0.79;

(5)4×8.8×0.25,

=4×0.25×8.8,

=1×8.8,

=8.8;

(6)0.36×101,

=0.36×(100+1),

=0.36×100+0.36×1,

=36+0.36,

=36.36.

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