Question

The ratio of boys to girls in a class is 5 to 6 which is an equivalent. Ratio

Answer 1

There are many possible answers.
10:12
15:18
20:24
25:30
30:36

Answer 2

The easiest way to find an equivalent ratio is simply by timesing one number by something, and then timesing the other number by the same one.  

For example: 
5 X 2 = 10. 
6 X 2 = 12.  
5:2 = 10:12. 

5 X 3 = 15. 
6 X 3 = 18. 
5:2 = 15:18. 

Hope this helps :)