In a college entrance test, the average marks obtained by all 30 boys of the class is 5 less than the average marks obtained by all 20 girls of the class. If the average marks of the whole class are 25, then find the ratio of average marks of boys to that of girls.
1
28 ∶ 23
2
41 ∶ 32
3
32 ∶ 41
4
23 ∶ 28