题目内容

11.计算
(1)0-16+6-33;                                             
(2)-9-(-7)+(-6)-(+4)-(-5);
(3)(+3$\frac{2}{5}$)+(-2$\frac{7}{8}$)-(-5$\frac{3}{5}$)-(+$\frac{1}{8}$);      
(4)(-$\frac{3}{5}$)×(-$\frac{1}{2}$)÷(-$\frac{1}{4}$)÷3;
(5)($\frac{1}{3}$-$\frac{5}{21}$+$\frac{3}{14}$-$\frac{2}{7}$)÷(-$\frac{1}{42}$);                   
(6)(-25$\frac{4}{7}$)÷(-4);
(7)(-5)×(-3$\frac{6}{7}$)+(-7)×(-3$\frac{6}{7}$)-(-12)×(-3$\frac{6}{7}$);    
(8)|-2$\frac{1}{2}$|-(-2.5)+1-|1-2$\frac{1}{2}$|;
(9)(-2)3×8-8÷($\frac{1}{2}$)3+8÷$\frac{1}{8}$;          
(10)-14-(-5$\frac{1}{2}$)×$\frac{4}{11}$+(-2)3÷|-32+1|.

分析 (1)(2)(4)(8)(9)(10)根据有理数的混合运算的运算方法,求出每个算式的值各是多少即可.
(3)应用加法交换律和加法结合律,求出算式的值是多少即可.
(5)(7)应用乘法分配律,求出每个算式的值各是多少即可.
(6)应用除法的性质,求出算式的值是多少即可.

解答 解:(1)0-16+6-33
=-10-33
=-43
                                         
(2)-9-(-7)+(-6)-(+4)-(-5)
=-2-6-4+5
=-12+5
=-7

(3)(+3$\frac{2}{5}$)+(-2$\frac{7}{8}$)-(-5$\frac{3}{5}$)-(+$\frac{1}{8}$)
=(+3$\frac{2}{5}$)-(-5$\frac{3}{5}$)+(-2$\frac{7}{8}$)-(+$\frac{1}{8}$)
=9-3
=6

(4)(-$\frac{3}{5}$)×(-$\frac{1}{2}$)÷(-$\frac{1}{4}$)÷3
=$\frac{3}{10}$÷(-$\frac{1}{4}$)÷3
=(-$\frac{6}{5}$)÷3
=-$\frac{2}{5}$

(5)($\frac{1}{3}$-$\frac{5}{21}$+$\frac{3}{14}$-$\frac{2}{7}$)÷(-$\frac{1}{42}$)              
=($\frac{1}{3}$-$\frac{5}{21}$+$\frac{3}{14}$-$\frac{2}{7}$)×(-42)
=$\frac{1}{3}$×(-42)-$\frac{5}{21}$×(-42)+$\frac{3}{14}$×(-42)-$\frac{2}{7}$×(-42)
=-14+10-9+12
=-1

(6)(-25$\frac{4}{7}$)÷(-4)
=(-25-$\frac{4}{7}$)÷(-4)
=(-25)÷(-4)-$\frac{4}{7}$÷(-4)
=6$\frac{1}{4}$+$\frac{1}{7}$
=6$\frac{11}{28}$

(7)(-5)×(-3$\frac{6}{7}$)+(-7)×(-3$\frac{6}{7}$)-(-12)×(-3$\frac{6}{7}$)
=(-3$\frac{6}{7}$)×(-5-7+12)
=(-3$\frac{6}{7}$)×0
=0

(8)|-2$\frac{1}{2}$|-(-2.5)+1-|1-2$\frac{1}{2}$|
=2$\frac{1}{2}$+2.5+1-2$\frac{1}{2}$+1
=2$\frac{1}{2}$-2$\frac{1}{2}$+1+2.5+1
=4.5

(9)(-2)3×8-8÷($\frac{1}{2}$)3+8÷$\frac{1}{8}$    
=(-8)×8-8÷$\frac{1}{8}$+64
=-64-64+64
=-64

(10)-14-(-5$\frac{1}{2}$)×$\frac{4}{11}$+(-2)3÷|-32+1|
=-1+2-8÷8
=1-1
=0

点评 此题主要考查了有理数的混合运算,要熟练掌握,注意明确有理数混合运算顺序:先算乘方,再算乘除,最后算加减;同级运算,应按从左到右的顺序进行计算;如果有括号,要先做括号内的运算.

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