Question

急！！！百分数数学题，懂英语和数学的来！！！

there are 900 students in a school , and 405 of them are boys. Also, 60% of the students are in junior forms, and 306 of them are girls。
（a）What percentage of the students are girls in the school?
(b)What percentage of the senior students are girls?
(c)How many boys are there in senior forms?
答案我都知道，就是要算式

Answer 1

（a）（900-405）/900=55%
（b）（900-405-306）/（900*40%）=52.5%
（c) 900*40%*（1-52.5%）=171

Answer 2

一所学校有900名学生，他们中有405名是男生，还有，学生中60%在初中，其中有306名是女生。
问题1在学校里女生占比多少？
问题2在高中部女生占比多少？这个问题问的有点不明白啊。占比范围没说明白啊。
问题3在高中部男生多少名？
1、女生人数占比为900-405/900=0.55
2、495-306=189名
3、405-（900*60%-306）= 171名

Answer 3

（a）What percentage of the students are girls in the school?
(900-405)/900=0.55=55%
(b)What percentage of the senior students are girls?
306/(900*60%)=306/540=56.66%
(c)How many boys are there in senior forms?
900*60%-306=540-306=234

Answer 4

（1）55%
（2）57%
（3）44%

Answer 5

1,55%
2,52.5%
3,171