Multiply each ratio by 5: 6:10:14; now reduce by dividing each ratio by 2:
3:5:7 is the simplest reduction not involving fractions.
3+5+7=15, so if we have a line 15 units long, then split it into three sections, 3, 5 and 7 units long, the ratio of these lengths is 1.2:2:2.8. We can take any pair of these to find the ratio between them:
3:5, 3:7, 5:7.