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八年级数学填空题一般
题目
一个四位数若满足各个数位的数字均不为零,千位数字不等于十位数字,且千位数字与百位数字的和等于十位数字与个位数字的和,则称其为"有序等和数".最小的"有序等和数"为______;;已知M=1000a+200b+120c+d+2(aM=1000a+200b+120c+d+2(a,bb,cc,dd为整数,1a9,12b+c9,1c,d4,)1\leqslant a\leqslant 9,1\leqslant 2b+c\leqslant 9,1\leqslant c,d\leqslant 4,)为"有序等和数",将MM的千位数字作为十位数字,MM的十位数字作为个位数字得到的两位数记为ss,将MM的百位数字作为十位数字,MM的个位数字作为个位数字得到的两位数记为tt,记F(M)=a2+bc25F\left(M\right)=a^{2}+b-c^{2}-5,G(M)=a+b+c2c+dG(M)=\frac{a+b+c}{2c+d},若s+ts+t99整除余22,且66F(M)\frac{66}{F(M)}为整数,求所有满足条件的G(M)G\left(M\right)的和为______.
知识点:一元一次不等式组的整数解、由实际问题抽象出一元一次不等式组章节:未标注

答案与解析

答案

\because最小的四位数的千位数字为11,各个数位的数字均不为零,
1+2=2+11+2=2+1
\therefore最小“有序等和数”为12211221
M=1000a+200b+120c+d+2=1000a+100(2b+c)+10×2c+d+2\because M=1000a+200b+120c+d+2=1000a+100\left(2b+c\right)+10\times 2c+d+21a91\leqslant a\leqslant 912b+c91\leqslant 2b+c\leqslant 91c1\leqslant cd4d\leqslant 4
M\therefore M的千位数为aa,百位数为2b+c2b+c,十位数为2c2c,个位数为d+2d+2
M\because M为“有序等和数”,
a+2b+c=2c+d+2\therefore a+2b+c=2c+d+2,即a+2b=c+d+2a+2b=c+d+2,且a2ca\neq 2c
s=10a+2c\therefore s=10a+2ct=10(2b+c)+(d+2)t=10\left(2b+c\right)+\left(d+2\right)
s+t=10a+2c+20b+10c+d+2=10a+20b+12c+d+2=9a+18b+9c+a+2b+3c+d+2\therefore s+t=10a+2c+20b+10c+d+2=10a+20b+12c+d+2=9a+18b+9c+a+2b+3c+d+2
s+r\because s+r99整除余22
a+2b+3c+d\therefore a+2b+3c+d能被99整除,
a+2b+c=2c+d+2\because a+2b+c=2c+d+2
a+2b+3c+d=a+2b+c+2c+d=(2c+d+2)+2c+d=4c+2d+2\therefore a+2b+3c+d=a+2b+c+2c+d=\left(2c+d+2\right)+2c+d=4c+2d+2
1a9\because 1\leqslant a\leqslant 912b+c91\leqslant 2b+c\leqslant 91c1\leqslant cd4d\leqslant 44c+2d+24c+2d+2能被99整除,
4c+2d+2=9k4c+2d+2=9k,则84c+2d+2458\leqslant 4c+2d+2\leqslant 45
1<k5\therefore 1 \lt k\leqslant 5.
d=9k24c2d=\frac{9k-2-4c}{2}
d4\because d\leqslant 4
Y=66F(M)Y=\frac{66}{F(M)}
①当d=4d=4时,4c+2d+2=10+4c4c+2d+2=10+4c能被99整除,c=2c=2,则a4a\neq 4
a+2b=c+d+2=8\therefore a+2b=c+d+2=80.5b35-0.5\leqslant b\leqslant 35
{a=2b=3\therefore \left\{\begin{array}{l}{a=2}\\{b=3}\end{array}\right.{a=6b=1\left\{\begin{array}{l}{a=6}\\{b=1}\end{array}\right.{a=8b=0\left\{\begin{array}{l}{a=8}\\{b=0}\end{array}\right.
F(M)=a2+bc25F\left(M\right)=a^{2}+b-c^{2}-5
a=2a=2b=3b=3c=2c=2时,F(M)=4+345=2F\left(M\right)=4+3-4-5=-2YY为整数,则G(M)=a+b+c2c+d=2+3+22×2+4=78G\left(M\right)=\frac{a+b+c}{2c+d}=\frac{2+3+2}{2×2+4}=\frac{7}{8}
a=6a=6b=1b=1c2c-2时,F(M)=36+145=28F\left(M\right)=36+1-4-5=28YY不为整数,舍去,
a=8a=8b=0b=0c=2c=2时,F(M)=64+045=55F\left(M\right)=64+0-4-5=55YY不为整数,舍去,
②当d=3d=3时,4c+2d+2=8+4c4c+2d+2=8+4c能被99整除,c=7c=7.
a+2b=c+d+2=11\therefore a+2b=c+d+2=113b1-3\leqslant b\leqslant 1
{a=9b=1\therefore \left\{\begin{array}{l}{a=9}\\{b=1}\end{array}\right.91+39-1+3
F(M)=a2+bc25\therefore F\left(M\right)=a^{2}+b-c^{2}-5
a=9a=9b=1b=1c=7c=7时,F(M)=81+1495=28F\left(M\right)=81+1-49-5=2866F(M)\frac{66}{F(M)}不为整数,舍去,
③当d=2d=2时,4c+2d+2=6+4c4c+2d+2=6+4c能被99整除,c=3c=3,:a+2b=c+d+2=7a+2b=c+d+2=71b2-1\leqslant b\leqslant 2
a=3a=3b=2b=2c=3c=3时,F(M)9+295=3F\left(M\right)-9+2-9-5=-3YY为整数,则G(M)=1G\left(M\right)=1
a=5.b=1a=5.b=1c=3c=3时,F(M)=25+195=12F\left(M\right)=25+1-9-5=12YY不为整数,舍去,
a=7a=7b=0.c=3b=0.c=3时,F(M)=49+095=35.YF\left(M\right)=49+0-9-5=35.Y为整数,舍去,
a=9.b=1a=9.b=-1c=3c=3时,F(M)81+195=66F\left(M\right)-81+1-9-5=66YY为整数,则G(M)=91+32×3+2=118G\left(M\right)=\frac{9-1+3}{2×3+2}=\frac{11}{8}
④当d=1d=1时,4c+2d+24+4c4c+2d+2-4+4c能被99整除,c=8c=8,:a+2b=c+d+2=11\therefore a+2b=c+d+2=11
b=2b=2a=9a=9
12b+891\leqslant 2b+8\leqslant 9,可知,aabb的值不符合题意,应舍去,
⑤当d=0d=0时,4c+2d+2=2+4c4c+2d+2=2+4c能被99整除,c=4c=4,则a8a\neq 8,:a+2b=c+d+2=6a+2b=c+d+2=615b25-15\leqslant b\leqslant 25
a=2a=2h=2h=2c=4c=4时,F(M)=4+2165=15.YF\left(M\right)=4+2-16-5=-15.Y不为整数,舍去,
a=4.h=1a=4.h=1c=4c=4时,F(M)=16+1165=4.YF\left(M\right)=16+1-16-5=-4.Y不为整数,舍去.
\therefore所有满足条件的G(M)G\left(M\right)的和为78+1+118=134\frac{7}{8}+1+\frac{11}{8}=\frac{13}{4}.
故答案为:134\frac{13}{4}.

解析

\because最小的四位数的千位数字为11,各个数位的数字均不为零,
1+2=2+11+2=2+1
\therefore最小“有序等和数”为12211221
M=1000a+200b+120c+d+2=1000a+100(2b+c)+10×2c+d+2\because M=1000a+200b+120c+d+2=1000a+100\left(2b+c\right)+10\times 2c+d+21a91\leqslant a\leqslant 912b+c91\leqslant 2b+c\leqslant 91c1\leqslant cd4d\leqslant 4
M\therefore M的千位数为aa,百位数为2b+c2b+c,十位数为2c2c,个位数为d+2d+2
M\because M为“有序等和数”,
a+2b+c=2c+d+2\therefore a+2b+c=2c+d+2,即a+2b=c+d+2a+2b=c+d+2,且a2ca\neq 2c
s=10a+2c\therefore s=10a+2ct=10(2b+c)+(d+2)t=10\left(2b+c\right)+\left(d+2\right)
s+t=10a+2c+20b+10c+d+2=10a+20b+12c+d+2=9a+18b+9c+a+2b+3c+d+2\therefore s+t=10a+2c+20b+10c+d+2=10a+20b+12c+d+2=9a+18b+9c+a+2b+3c+d+2
s+r\because s+r99整除余22
a+2b+3c+d\therefore a+2b+3c+d能被99整除,
a+2b+c=2c+d+2\because a+2b+c=2c+d+2
a+2b+3c+d=a+2b+c+2c+d=(2c+d+2)+2c+d=4c+2d+2\therefore a+2b+3c+d=a+2b+c+2c+d=\left(2c+d+2\right)+2c+d=4c+2d+2
1a9\because 1\leqslant a\leqslant 912b+c91\leqslant 2b+c\leqslant 91c1\leqslant cd4d\leqslant 44c+2d+24c+2d+2能被99整除,
4c+2d+2=9k4c+2d+2=9k,则84c+2d+2458\leqslant 4c+2d+2\leqslant 45
1<k5\therefore 1 \lt k\leqslant 5.
d=9k24c2d=\frac{9k-2-4c}{2}
d4\because d\leqslant 4
Y=66F(M)Y=\frac{66}{F(M)}
①当d=4d=4时,4c+2d+2=10+4c4c+2d+2=10+4c能被99整除,c=2c=2,则a4a\neq 4
a+2b=c+d+2=8\therefore a+2b=c+d+2=80.5b35-0.5\leqslant b\leqslant 35
{a=2b=3\therefore \left\{\begin{array}{l}{a=2}\\{b=3}\end{array}\right.{a=6b=1\left\{\begin{array}{l}{a=6}\\{b=1}\end{array}\right.{a=8b=0\left\{\begin{array}{l}{a=8}\\{b=0}\end{array}\right.
F(M)=a2+bc25F\left(M\right)=a^{2}+b-c^{2}-5
a=2a=2b=3b=3c=2c=2时,F(M)=4+345=2F\left(M\right)=4+3-4-5=-2YY为整数,则G(M)=a+b+c2c+d=2+3+22×2+4=78G\left(M\right)=\frac{a+b+c}{2c+d}=\frac{2+3+2}{2×2+4}=\frac{7}{8}
a=6a=6b=1b=1c2c-2时,F(M)=36+145=28F\left(M\right)=36+1-4-5=28YY不为整数,舍去,
a=8a=8b=0b=0c=2c=2时,F(M)=64+045=55F\left(M\right)=64+0-4-5=55YY不为整数,舍去,
②当d=3d=3时,4c+2d+2=8+4c4c+2d+2=8+4c能被99整除,c=7c=7.
a+2b=c+d+2=11\therefore a+2b=c+d+2=113b1-3\leqslant b\leqslant 1
{a=9b=1\therefore \left\{\begin{array}{l}{a=9}\\{b=1}\end{array}\right.91+39-1+3
F(M)=a2+bc25\therefore F\left(M\right)=a^{2}+b-c^{2}-5
a=9a=9b=1b=1c=7c=7时,F(M)=81+1495=28F\left(M\right)=81+1-49-5=2866F(M)\frac{66}{F(M)}不为整数,舍去,
③当d=2d=2时,4c+2d+2=6+4c4c+2d+2=6+4c能被99整除,c=3c=3,:a+2b=c+d+2=7a+2b=c+d+2=71b2-1\leqslant b\leqslant 2
a=3a=3b=2b=2c=3c=3时,F(M)9+295=3F\left(M\right)-9+2-9-5=-3YY为整数,则G(M)=1G\left(M\right)=1
a=5.b=1a=5.b=1c=3c=3时,F(M)=25+195=12F\left(M\right)=25+1-9-5=12YY不为整数,舍去,
a=7a=7b=0.c=3b=0.c=3时,F(M)=49+095=35.YF\left(M\right)=49+0-9-5=35.Y为整数,舍去,
a=9.b=1a=9.b=-1c=3c=3时,F(M)81+195=66F\left(M\right)-81+1-9-5=66YY为整数,则G(M)=91+32×3+2=118G\left(M\right)=\frac{9-1+3}{2×3+2}=\frac{11}{8}
④当d=1d=1时,4c+2d+24+4c4c+2d+2-4+4c能被99整除,c=8c=8,:a+2b=c+d+2=11\therefore a+2b=c+d+2=11
b=2b=2a=9a=9
12b+891\leqslant 2b+8\leqslant 9,可知,aabb的值不符合题意,应舍去,
⑤当d=0d=0时,4c+2d+2=2+4c4c+2d+2=2+4c能被99整除,c=4c=4,则a8a\neq 8,:a+2b=c+d+2=6a+2b=c+d+2=615b25-15\leqslant b\leqslant 25
a=2a=2h=2h=2c=4c=4时,F(M)=4+2165=15.YF\left(M\right)=4+2-16-5=-15.Y不为整数,舍去,
a=4.h=1a=4.h=1c=4c=4时,F(M)=16+1165=4.YF\left(M\right)=16+1-16-5=-4.Y不为整数,舍去.
\therefore所有满足条件的G(M)G\left(M\right)的和为78+1+118=134\frac{7}{8}+1+\frac{11}{8}=\frac{13}{4}.
故答案为:134\frac{13}{4}.

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