用英语出的数学题 20道

小学六年级

1. 40% of the students in a school are boys.lf there are 240 boys, how many student are therein the school?
2. a boy has finished reading 160pages of a story book and he finds that is 20% of the book left.how many pages are there in the book?
3. Among the 800 people, 70% like swimming.How many people like swimming?

1、学校40%的学生是男孩，如果这里有240个男孩，那么学校有多少学生？
240/40%=600
2、一个男孩看完了160页故事书，他发现还有20%没看，问这本故事书多少页？ 160/（1-20%0）=200
3、800人中，70%的人喜欢游泳，请问有多少人喜欢游泳？
800*70%=560

how old is the captain,how many children has he,and howlogn is his boat?given the product 32118 of the three desired numbers(integers).the length of the boat is given in feet(is several feet),the captain has both sons and daughters,he has more years than children,but he is not yet one hundred years ols.(give reasons for your answer.)

解答：the captian is 31 years old.the captain has 2 children.the boat is 81 feet long. reason: the number of children should be a number less than 10, so the age of the captain and the length of the boat should be both double-digit. and a boat should be more than 30 feet, so, the boat should be 8x feet. the captain has he has both sons and daughters, so we have to choose from 3 and 2 .if we choose 3, then the age of captain should be choosen from 21 11, and 12(8 is left for the boat length).they are too young for a father of three children, so 3 is abandoned.then we can draw the conclusion that the captain has 2 children. the possible answer for the capitain's age are 31,11and13. definitely, we abandon 11 and 13, so the captain is 31. then only one number is left,i.e.1, so the length of the boat is 81 feet. 不知道对不对哈.过程和答案我都给出来了,嘿嘿,自己判断吧. 中文大意就是,这个船长既有女儿又有儿子,而且他比他的儿女大很多,但是还不到一百岁,这个船的长度是以英尺计的.给出了六个数,32118,组成整数,回答问题:船长多大了,有几个孩子,船长是多少. 答案;船长31岁,2个孩子,船的长度是81英尺. 思路大概是这样的,孩子的数目应该是一位数的,船长的年龄是两位数,所以船的长度也是两位数,那么可能的船的长度的十位数就只能是8. 船长儿女双全,所以孩子的个数应该是2或3,如果是3个孩子的话,那么船长的年龄就只剩下了21,12和11三个选择,这显然都太年轻,所以排除3,船长有2个孩子. 那么船长的年龄就应该是31,11或是13,显然,31是唯一合理的选择. 这样船的长度也出来了,是81英尺. (一英尺等于12英寸,一英寸等于25.4毫米,一英尺就是30多厘米.)