问题 解答题
用合理灵活的方法计算.
30.9÷[14-(9.85+1.15)]1.2×7.26+1.2×2.740.25×32×12.5
21.14+9.2×1.37.8÷0.15÷47.1×101.
答案

(1)30.9÷[14-(9.85+1.15)]

=30.9÷[14-11]

=30.9÷3

=10.3;

(2)1.2×7.26+1.2×2.74

=1.2×(7.26+2.74)

=1.2×10

=12;

(3)0.25×32×12.5

=(0.25×4)×(8×12.5)

=1×100

=100;

(4)21.14+9.2×1.3

=21.14+11.96

=33.1;

(5)7.8÷0.15÷4

=52÷4

=13;

(6)7.1×101

=7.1×(100+1)

=7.1×100+7.1

=710+7.1

=717.1.

单项选择题
单项选择题