Yes, the two ratios are proportional to each other. The multiplier from the first ratio to the second ratio is 3. For example, 4.2 x 3 = 12.6 and 1.5 x 3 = 4.5. Basically, to figure out if two ratios are proportional to each other, just divide the smaller number into the bigger number for both corresponding numbers. If they're the same ---> Proportional. If they're not the same ---> Not Proportional