英语应用题一题(需要解题步骤)Class A and Class B have the same number of students.In Class A,the ratio of boys to girls is 3 to 2.In Class B,the number of boys is 200% of the number of girls.If one girl in Class A and one boy in Class B s

英语应用题一题(需要解题步骤)Class A and Class B have the same number of students.In Class A,the ratio of boys to girls is 3 to 2.In Class B,the number of boys is 200% of the number of girls.If one girl in Class A and one boy in Class B s
英语应用题一题(需要解题步骤)
Class A and Class B have the same number of students.In Class A,the ratio of boys to girls is 3 to 2.In Class B,the number of boys is 200% of the number of girls.If one girl in Class A and one boy in Class B switch classes,the ratios of boys to girls in both classes will be the same.Find the numbers of boys and girls in the two classes.Show all your work.

英语应用题一题(需要解题步骤)Class A and Class B have the same number of students.In Class A,the ratio of boys to girls is 3 to 2.In Class B,the number of boys is 200% of the number of girls.If one girl in Class A and one boy in Class B s
先翻成中文吧这样就容易明白多了
A 班和B班所有的学生人数相同,A班的男孩和女孩的人数比例是3比2,B班的男孩是女孩人数的200%.如果让A班的一个女孩和B班的一个男孩换班,那么A,B两班的男孩和女孩的人数比例就相等,求两班的男孩和女孩的人数
设A班男生人数为X,那么A班女生人数是（2/3）X
再设B班男生人数为Y,那么B班女生人数是 Y/2,可得出方程组
X+（2/3）X=Y+ Y/2
（X+1）：[（2/3）X-1]=（Y-1）：（Y/2+1）
由方程1得出 （5/3）X=（3/2）Y,10X=9Y,X=（9/10）Y
代入方程2得出 [(9/10)Y+1]：[(2/3)*(9/10)Y-1]=(Y-1):(Y/2+1)
解方程得 Y=20 或Y=0,由于Y=0没意义,所以B班男生人数是20
则B班女生人数是20/2=10
A班男生人数是 （9/10）Y=18,A班女生人数是（2/3）*18=12
终上所述,A班男生人数是18人,女生人数是12人
B班男生人数是20人,女生人数是10人

Assume there are 2x girls in Class A, and there are 3x boys in Class A. Assume there are y girls in class B, and there are 2y girls in Class B. According to the discription, we have an equation: 2x...

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Assume there are 2x girls in Class A, and there are 3x boys in Class A. Assume there are y girls in class B, and there are 2y girls in Class B. According to the discription, we have an equation: 2x-1/3x 1=y 1/2y-1
And we have: 5x=3y
And x=6, y=10.
So there are 18boys and 12girls in Class A.
And 20 boys and 10 girls in Class B

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和GMAT的数学题很相似

There are 30 students in each class. 3:2 and 2:1 We can know the number students of each class should be at least 15 persons. and if they switch a boy and a girl, the ratios will be the same We can kn...

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There are 30 students in each class. 3:2 and 2:1 We can know the number students of each class should be at least 15 persons. and if they switch a boy and a girl, the ratios will be the same We can know boys in class B should be two more than in Class A. 15X2=30. so the boys in class A should be 18 persons. The boys in Class B should be 20 persons.

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我帮你把方程列出来吧：
有四个未知数，x1, A班男生 x2,A班女生 x3, B班男生 x4， B班女生
x1 + x2 = x3 + x4
x1 : x2 = 3:4
x3 = x4 * 200%
(x1+1): (x2-1) = (x3-1) : (x4+1)