挑战习题
1
/5
单选题
难度:
1.用不等式表示a的一半与2的差大于-1,正确的是( )
A
(
a
−2)>−1
B
a
-2>-1
C
(a-2)≥-1
D
a-2<-1
提示1:
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正确答案:
Qg==
6Kej77ya5qC55o2u6aKY5oSP77yM5b6XPGltZyB3aWR0aD01IGhlaWdodD00MiBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzAwLzBDL3JCQUNGRk5zU2RuQ2Z1b29BQUFCR2FqMnNOUTgwMC5wbmciPmEtMu+8ni0xLiA8YnI+5pWF6YCJ77yaQi4g
2
/5
单选题
难度:
2.下列说法错误的是( )
A
a是负数,则写作a<0
B
a与b的积小于0,则写作ab<0
C
b不小于0,则写作b≥0
D
x不小于y,则写作x≤y
提示1:
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正确答案:
RA==
6Kej77yaQeOAgWHmmK/otJ/mlbDvvIzliJnlhpnkvZxh77ycMO+8jOaVheacrOmAiemhueS4jeespuWQiOmimOaEj++8mzxicj5C44CBYeS4jmLnmoTnp6/lsI/kuo4w77yM5YiZ5YaZ5L2cYWLvvJww77yM5pWF5pys6YCJ6aG55LiN56ym5ZCI6aKY5oSP77ybPGJyPkPjgIFi5LiN5bCP5LqOMO+8jOWImeWGmeS9nGLiiaUw77yM5pWF5pys6YCJ6aG55LiN56ym5ZCI6aKY5oSP77ybPGJyPkTjgIF45LiN5bCP5LqOee+8jOWwseW6lOivpeaYr+Wkp+S6juetieS6jnnvvIzlupTorrDkvZx44omleS4g5omA5Lul5pys6YCJ6aG556ym5ZCI6aKY5oSPLiA8YnI+5pWF6YCJRC4g
3
/5
单选题
难度:
3.一个数x的
与-4的差不小于这个数的2倍加上5所得的和,则可列不等式为( )
A
x-4>2x+5
B
x+4>2x+5
C
x-4≥2x+5
D
x+4≥2x+5
提示1:
IOeQhuino+WFs+mUruivjeivre+8muS4jeWwj+S6jueahOaEj+aAneaYr+Wkp+S6juaIluetieS6ju+8m+S4ji0055qE5beu5piv5YeP5Y67LTTlrp7pmYXnrYnkuo7liqDkuIo0Lg==
正确答案:
RA==
6Kej77ya5qC55o2u6aKY5oSP77yM5b6XPGltZyB3aWR0aD01IGhlaWdodD00MiBzcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzAwLzBDL3JCQUNGRk5zU2VHeHdFN3NBQUFCSG9Gd3pRczY1Mi5wbmciPngrNOKJpTJ4KzUuIDxicj7mlYXpgIlELiA=
4
/5
单选题
难度:
4.小明身高1.5米,小明爸爸身高1.8米,小明走上一处每级高a米,共10级的平台说:“爸爸,现在两个你的身高都比不上我了!”由此可得关于a的不等式是( )
A
1Oa>1.8×2
B
1.5+a+10>1.8×2
C
10a+1.5>1.8×2
D
1.8×2>10a+15
提示1:
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正确答案:
Qw==
6Kej77ya5qC55o2u6aKY5oSP77yM5b6XMTBhKzEuNe+8njEuOMOXMi4gPGJyPuaVhemAie+8mkMuIA==
5
/5
单选题
难度:
5.有盐水84kg,含盐12%,为使盐水含盐不低于24%,至少应加盐多少千克设应加盐x(kg),由题意列不等式为( )
A
84×12%+x≥(84+x)×24%
B
(84-x)×12%>(84+x)×24%
C
(84+x)×12%≤84×24%+x
D
84×12%+x>(84+x)×24%
提示1:
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提示2:
DQrkuI3nrYnlhbPns7vvvJrnm5DmsLTlkKvnm5DkuI3kvY7kuo4yNCXvvIzljbPnuq/nm5DnmoTotKjph4/kuI3kvY7kuo7mgLvotKjph4/nmoQyNCUu
正确答案:
QQ==
6Kej77ya5qC55o2u6aKY5oSP77yM5b6XPGJyPjg0w5cxMiUreOKJpe+8iDg0K3jvvInDlzI0JTxicj7mlYXpgIlBLiA=