The ratio of blue pens to black pens on a teacher's desk is 4 to 6. A teacher asks four students to write an equivalent ratio to 4 to 6. The table shows each student's response.
Student
1
2
3
4
Response
8:10
6:12
10:15
9:12
Which student is correct?
Student 1
Student 2
Student 3
Student 4