下午2点30分时，时钟的分针与时针所成角的度数为______．

解题思路：因为钟表上的刻度是把一个圆平均分成了12等份，每一份是30°，借助图形，找出时针和分针之间相差的大格数，用大格数乘30°即可．

∵时针在钟面上每分钟转0.5°，分针每分钟转6°，
∴钟表上下午2点30分时，时针与分针的夹角可以看成时针转过2时0.5°×30=15°，分针在数字6上．
∵钟表12个数字，每相邻两个数字之间的夹角为30°，
∴下午2点30分时分针与时针的夹角4×30°-15°=105°．
故答案为：105°．

点评：
本题考点： 钟面角．

考点点评： 本题考查钟表分针所转过的角度计算．在钟表问题中，常利用时针与分针转动的度数关系：分针每转动1°时针转动（[1/12]）°，并且利用起点时间时针和分针的位置关系建立角的图形．

After coming out of the airport,it costed me 30 minutes to arrive to the hotel by taxi!i signed in at the hotel by 2:30 in the afternoon!They didn't offer lunch on the airplane,so i ate a salad at 3 o'clock.Mike rushed to come having dinner with me from La Jolla.We ate dinner at the hotel and that was a very wonderful night!

1、Daniel is showing his uncle around Sunshine Secondary School.
2、Can you come to the parents' meeting on 9th December?
3、The school open day starts at 2:30 in the afternoon.
4、Please show me around your school!到某人参观某地show sb around sp
5、The students often have meetings in the school hall.
6、Sally sits in the front of the classroom.
若有需要详细讲解的或者不懂的就追问吧!）

Normally,the cross check report should be received before 09:00 a.m.,however,we did not receive it until 02:30 p.m.that afternoon.

要使数学成绩超过别人,技巧是：
1,细心：如有分类讨论的千万不要遗漏每一种可能的情况.
2,全面：考虑问题要全面.
3,思考要慎密,书写要清楚.
4,正难则反,如遇难题要退一步思考,转换一下思考角度.