问题 解答题
递等式计算(能巧则巧)
9.9×1.017.8÷1.25×8
0.25×(12-3.96÷18)0.24×15÷(3.25-2.35)
3.4×7.5+7.5×7.6-7.5.
答案

(1)9.9×1.01,

=9.9×(1+0.01),

=9.9+0.099,

=9.999;

(2)7.8÷1.25×8,

=6.24×8,

=49.92;

(3)0.25×(12-3.96÷18),

=0.25×(12-0.22),

=0.25×12-0.25×0.22,

=0.25×4×3-0.25×4×0.055,

=3-0.055,

=2.945;

(4)0.24×15÷(3.25-2.35),

=0.24×15÷0.9,

=3.6÷0.9,

=4;

(5)3.4×7.5+7.5×7.6-7.5,

=(3.4+7.6-1)×7.5,

=10×7.5,

=75.

选择题
单项选择题