并请用汉语写出你从故事中得到的启示（共计10分）

　　A boy and a girl were playing together. The boy had a collection of marbles(弹珠）The girl had some delicious sweets with her.

　　The boy told the girl that he will give her all his marbles in exchange(交换）for her sweets. The girl agreed. The boy kept the biggest and the most beautiful marble aside and gave the rest to the girl. The girl gave him all her sweets as she had promised(承诺).That night, the girl slept very well. But the boy couldn't sleep as he kept thinking if the girl had hidden some sweets form him the way he had hidden(藏）his best marble.

　　写出你从故事中得到的启示：要求字数不超过120个字，字里行间不得使用自己的姓名、学校等信息（共计10分）。

　　五、按要求完成下列各题。（共计30分）

　　1.There are some chickens and rabbits in a cage(笼子）.You can see 9 heads at the top and 24 feet at the bottom. How many chickens and rabbits are there in the cage?(可用汉语列式计算。6分）

　　2.100 students were in a math contest(竞赛）.The average（平均数） of their final score（分数） is 63.The average of the boy's score is 60.The average of the girl's score is 70.How many of them are boys? How many of them are girls?(可用汉语列式计算。8分）

　　3.Jack and Jim are friends. The ratio(比）of Jack's and Jim's pocket money is 3:2.If Jack gives Jim 10 yuan, the ratio of their pocket money will become 5:4.So how much money does Jack have?(可用汉语列式计算。8分）

　　4.Mike has a lot of apples. He needs to get them to town and sell them. It takes(花费）3 days to get all the apples to town with 8 big trucks. It takes 8days to get 75% of the apples to town with 5 small trucks. Now Mike has 3 big trucks and 4 small trucks, how many days will it take to get all the apples to town?(可用汉语列式计算。8分）