8:4 6:4 8:2 6:3 biggest ratio

Easy, make the ratios as a decimal. 8:4=2, 6:4=1.5, 8:2=4, and 6:3=2. Now, we have 2, 1.5, and 4, and 2. We can eliminate 8:4 and 6:3 since they are the same ratios, 1.5 equals 1.50, 4=4. Ask your self. Is 1.50 greater than 4? Well your answer is no. 4 is greater than 1.50. So, the biggest ratio is 8:2

8:2 is the biggest ratio, because if you reduce each ratio to the smallest ratio 4:1 is the biggest. 8:4 = 2:1 ... 6:4 = 3:2 ... 8:2 = 4:1 ... 6:3 = 2:1 ...