[2.25+(335÷1.8-1.21×511)]÷40%

问题描述:

[2.25+(3

3
5
÷1.8-1.21×
5
11
)]÷40%

[2.25+(3

3
5
÷1.8-1.21×
5
11
)]÷40%,
=[2.25+(
18
5
÷
9
5
-0.55)]÷40%,
=[2.25+(
18
5
×
5
9
-0.55)]÷40%,
=[2.25+(2-0.55)]÷40%,
=[2.25+(2-0.55)]÷40%,
=3.7÷0.4,
=9.25.
答案解析:先算小括号内的除法和乘法,再算小括号内的减法,然后算中括号内的加法,最后算括号外的除法.
考试点:整数、分数、小数、百分数四则混合运算.
知识点:考查了小数、分数的四则混合运算,注意运算顺序和运算法则.