Hi there! Just by looking at the choices, we can eliminate C and D, because those answers don’t make sense and they don’t flow together. 3:5 is equivalent to those like 6:10, 9:15, 12:20, and so on. You can basically add 3 and 5 in order to get the next ratios. The only ratio that works in this problem is B. The answer is B: 9:15.
