35/10 = 7/5
35*5 = 10*7 ... cross multiply
175 = 70
the last equation is false so the first equation is false. The original two ratios are NOT proportional
Another way to see this is to use a calculator to get the decimal form of each fraction
35/10 = 3.5
7/5 = 1.4
The results 3.5 and 1.4 are not the same so this is more confirmation that they are not proportional