There are 42 pupils in each of the slasses,primary 5A and primary 5B.The ratio of the number of boys in primary 5A to the number of boys in primary 5B was 3;4.The ratio of the number of girls inprimary 5A to the number of girls in primary 5B,was 4;3,There were 56 boys altogether in both classes.What was the ratio of boys in primary 5A to the number of girls in primary 5B?女儿翻译是；五年级A，B两班各有42名学生，5A和5B的男生比例是3；4，5A和5B女生的比例是4；3，两班男生共有56人，问5A男生和5B女生的比例？
如果答案是1；1的话男生总数不是56，如果是女儿算的12；5的话5A和5B的女生比例就不是4；3，所以我怀疑题目出错，请高手指点
这道题的确实有问题。“The ratio of the number of boys in primary 5A to the number of boys in primary 5B was 3：4”或“The ratio of the number of girls inprimary 5A to the number of girls in primary 5B,was 4：3″这两个条件拿掉任何一个这道题都能成立，放在一起就不行了。
有两种做法, 两个不同的答案。
方法1
Total units of boys –> 3+4=7Each units –> 56/7=8Nos of boys in 5A –> 8×3 =24Nos of boys in 5B –> 8×4 =32Nos of girls in 5B –> 42-32=10Nos of girls in 5A –> 42-24 =18
Ratio of boys in 5A to girls in primary 5B –> 24:10 = 12：5
方法2Nos of girls –> 42×2-56 =28Total units of girls –> 28/(4+3)=4Nos of girls in 5A –> 4×3 =12Nos of girls in 5B –> 4×4 =16Nos of boys in 5A –> 42-12=30Nos of boys in 5B –> 42-16=26
Ratio of boys in 5A to girls in primary 5B –>30:16=15：8