分析:(1)先算小括號(hào)里面的加法,再算小括號(hào)外面的乘法和加法;
(2)先算小括號(hào)里面的加法,再算中括號(hào)里面的減法,最后算括號(hào)外面的除法;
(3)先算小括號(hào)里面的加法,再算小括號(hào)外面的除法;
(4)先將除法變?yōu)槌朔,再約分計(jì)算即可;
(5)先算乘法,再算加法;
(6)先算小括號(hào)里面的加法,再算小括號(hào)外面的乘法和加法;
(7)根據(jù)連減的簡(jiǎn)算方法計(jì)算即可求解;
(8)根據(jù)乘法分配律計(jì)算即可求解.
解答:
解:(1)+(+)×, =+×, =+, =1; |
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(2)[1-(+)]÷, =[1-]÷, =÷, =1;
(3)(+)÷, =×, =4; |
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(4)÷××4, =×8××4, =10;
(5)+×+ =++, |
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=+(+), =+1, =1;
(6)×(+)+, =×+×+, =2+1+, =2+2, =4;
(7)11-3-2, =11-(3+2), =11-6, =5;
(8)3.87÷-0.87×, |
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=3.87×
-0.87×
,
=(3.87-0.87)×
,
=3×
,
=2.
點(diǎn)評(píng):此題是考查四則混合運(yùn)算,要仔細(xì)觀察算式的特點(diǎn),靈活運(yùn)用一些定律進(jìn)行簡(jiǎn)便計(jì)算.