Express the ratio 1.5:2.5:3.51.5 : 2.5 : 3.51.5:2.5:3.5 in the form of a ratio of integers in simplest form.
1:2:31:2:31:2:3
3:5:73:5:73:5:7
15:25:3515:25:3515:25:35
6:10:146:10:146:10:14