问题
选择题
用0,1,2,3,4组成没有重复数字的全部五位数中,若按从小到大的顺序排列,则数字12340应是第( )个数.
A.6
B.9
C.10
D.8
答案
答案:C
比12340小的分三类:第一类是千位比2小为0,有个; 第二类是千位为2 ,百位比3小为0,有
个; 第三类是十位比4小为0,有1个.共有6+2+1=9个,所以12340是第10个数.
用0,1,2,3,4组成没有重复数字的全部五位数中,若按从小到大的顺序排列,则数字12340应是第( )个数.
A.6
B.9
C.10
D.8
答案:C
比12340小的分三类:第一类是千位比2小为0,有个; 第二类是千位为2 ,百位比3小为0,有
个; 第三类是十位比4小为0,有1个.共有6+2+1=9个,所以12340是第10个数.
完型填空。 | ||||
My father __1__ a good friend in the factory (工厂). He is sixty. He is an old man. All of the children like him. We call __2__ Uncle Sam. He __3__ from England. He __4__ in Sichuan. He can't __5__ Chinese. We teach him __6__. He __7__ us English. He __8__ work on Sundays. He __9__ making things. And he likes watching TV __10__ his children at night. | ||||
|