问题 解答题
脱式计算,能用简便方法计算的要用简便方法计算.
62×7.1+2.9

4.2×0.25

5.2×4.3+0.8×4.3.
答案

(1)62×7.1+2.9,

=440.2+2.9,

=443.1;

(2)4.2×0.25,

=(4+0.2)×0.25,

=4×0.25+0.2×0.25,

=1+0.05,

=1.05;

(3)5.2×4.3+0.8×4.3,

=(5.2+0.8)×4.3,

=6×4.3,

=25.8.

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