1. (2024·江阴月考)$99\dfrac{18}{19}×13=(100-\dfrac{1}{19})×13=1300-\dfrac{13}{19}$运用了(
A.加法交换律
B.乘法结合律
C.乘法分配律
D.乘法交换律和结合律
C
)A.加法交换律
B.乘法结合律
C.乘法分配律
D.乘法交换律和结合律
答案
1.C
2.(江阴月考)下列计算结果是72的是(
A.$-9÷ (-3)^{2}$
B.$(-9)^{2}÷ (-3^{2})$
C.$-(-2)^{3}× (-3)^{2}$
D.$-(-2^{2})× (-3)^{3}$
C
)A.$-9÷ (-3)^{2}$
B.$(-9)^{2}÷ (-3^{2})$
C.$-(-2)^{3}× (-3)^{2}$
D.$-(-2^{2})× (-3)^{3}$
答案
2.C
3.(江阴月考)若$\left|a-\dfrac{1}{2}\right|+(b+1)^2=0$,则$-4× a× b=$
2
。答案
3.2
4.(江宁区月考)计算:$\left|-3^{2}-2\right|-\left|-2^{3}+8\right|=$
11
.答案
4.11
5.计算:
(1)$(-48)÷\dfrac{7}{4}÷(-12)×\dfrac{7}{4}$;
(2)$(-\dfrac{1}{2}-\dfrac{2}{3}+\dfrac{3}{4})÷(-\dfrac{1}{12})$;
(3)$(-2)^{2}×7-(-3)×6-|-5|$;
(4)$[45-(\dfrac{7}{9}-\dfrac{11}{12}+\dfrac{5}{6})×36]÷5.$
(1)$(-48)÷\dfrac{7}{4}÷(-12)×\dfrac{7}{4}$;
(2)$(-\dfrac{1}{2}-\dfrac{2}{3}+\dfrac{3}{4})÷(-\dfrac{1}{12})$;
(3)$(-2)^{2}×7-(-3)×6-|-5|$;
(4)$[45-(\dfrac{7}{9}-\dfrac{11}{12}+\dfrac{5}{6})×36]÷5.$
答案
5.解:
(1) 原式$=[(-48)÷(-12)]×(\dfrac{4}{7}×\dfrac{7}{4})=4×1=4$.
(2) 原式$=(-\dfrac{1}{2}-\dfrac{2}{3}+\dfrac{3}{4})×(-12)=(-\dfrac{1}{2})×(-12)-\dfrac{2}{3}×(-12)+\dfrac{3}{4}×(-12)=6+8-9=5$.
(3) 原式$=4×7+18-5=28+18-5=41$.
(4) 原式$=[45-\dfrac{7}{9}×36-(-\dfrac{11}{12})×36-\dfrac{5}{6}×36]÷5=(45-28+33-30)÷5=(78-58)÷5=20÷5=4$.
(1) 原式$=[(-48)÷(-12)]×(\dfrac{4}{7}×\dfrac{7}{4})=4×1=4$.
(2) 原式$=(-\dfrac{1}{2}-\dfrac{2}{3}+\dfrac{3}{4})×(-12)=(-\dfrac{1}{2})×(-12)-\dfrac{2}{3}×(-12)+\dfrac{3}{4}×(-12)=6+8-9=5$.
(3) 原式$=4×7+18-5=28+18-5=41$.
(4) 原式$=[45-\dfrac{7}{9}×36-(-\dfrac{11}{12})×36-\dfrac{5}{6}×36]÷5=(45-28+33-30)÷5=(78-58)÷5=20÷5=4$.
6.(2024·昆山月考)计算$(-2)^{5}+(-2)^{4}$的值是(
A.$-2$
B.$(-2)^{5}$
C.$0$
D.$-2^{4}$
D
)A.$-2$
B.$(-2)^{5}$
C.$0$
D.$-2^{4}$
答案
6.D
7.(2024·锡山区月考)下列计算:①$-2-1=-1$;②$(-5\dfrac{1}{2})-(-5.5)=0$;③$(-36)÷2×\dfrac{1}{2}=-36$;④$(-\dfrac{3}{5})+\dfrac{3}{5}×(-1)=-1\dfrac{1}{5}$.其中正确的是(
A.①③
B.①④
C.②③
D.②④
D
)A.①③
B.①④
C.②③
D.②④
答案
7.D
8. (2024·鼓楼区月考)若$(\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{7}-\dfrac{1}{5})÷ 163=\dfrac{1}{210}$,则计算$80-163÷ (\dfrac{1}{2}+\dfrac{1}{3}+\dfrac{1}{7}-\dfrac{1}{5})$的结果是(
A.$-130$
B.$130$
C.$-290$
D.$290$
A
)A.$-130$
B.$130$
C.$-290$
D.$290$
答案
8.A
9.(江阴期中)定义一种新运算:$a※b=a+b-ab$,如$2※(-2)=2+(-2)-2×(-2)=4$,那么$(-1)※2=$
3
.答案
9.3
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