First, set up a ratio: \(\frac{30}{100} = \frac{15,680}{x}\)
The first fraction is the percentage (30% and \(\frac{30}{100}\) are the same thing) and the second is the loan payment (which is equal to the 30 in the first fraction) over their annual income (\(x\)).
First you divide $15,680 by 30, then multiply that quantity by 100. The value calculated then replaces \(x\) in your second fraction: \(\frac{30}{100} = \frac{15,680}{52,266.67}\)
