搜题请搜索小程序“爱下问搜题”
问题 解答题

三个两位数的和是40，如果每一个数的十位数与个位数互换，组成三个新的两位数，它们的和是多少？

答案

由于三个两位数的和是40，所以只有两种情况：

①若这三个数有一个十位为2，则一定是10、10、20，但是他们的十位与个位数交换不能构成两位数，否定．

②若这三个数的十位数都是1，则三个数的个位相加为10．

十位与个位数交换后，原来个位加起来为10，现在在十位上，所以相加和为100，

原来十位为三个1，现在变为个位是三个1，加起来的3，

所以结果是100+3=103．

答：它们的和是103．

填空题

数据库管理系统中，为了保证事务的正确执行，维护数据库的完整性，要求数据库系统维护以下事务特性： 【19】 、一致性、隔离性和持久性。
查看答案
单项选择题

This was one of my experiences (1) . When I was in my 30s, I was working for a large international company which had its head office in London. I was working in the (2) department.

The company had a training centre which was just outside London. Different courses were held there throughout (3) and I (4) go on one training course a year. These usually started (5) a Sunday evening and lasted six days.

Once I was (6) a week’s training course with about forty (7) sales people. I was in the bar on the Friday evening and suddenly a woman who was (8) behind the bar asked mea curious question. "I hope you don’t (9) my asking," she said, "but I’ve been (10) about it all week. Have you got a sister (11) Mary" The woman’s name was June. And she used to do various jobs at the training centre. She worked in the office, she organized all the food and drink for the centre and she worked in the bar at lunchtime and in the evening.

My answer (12) June’s question was "Yes", and June said, "I thought (13) . I met her last September when she was organizing a course here. " At that time, my sister was working for (14) company but in a different part of the country. That was (15) she came to be at the training centre.

(16) surprised me was how June guessed we were brother and sister. Three things made it even more (17) . First, she had met my sister six months before she met me. Second, they have about sixty new people every week at the training centre. So about one thousand five hundred people had (18) the centre in those six months. And (19) , my sister is married, so she doesn’t have the same family name as me.

We’re not (20) , but I guess we must look quite like each other.

18().

A．passed by

B．passed away

C．left

D．passed through
查看答案