How can you use proportional reasoning to solve problems involving percent

Example A, Step 1: Write a comparing the percent to the ratio of part to whole. ex- ?/25 = 28/100 *Notice that 25 is a factor of 100* Step 2: Find the multiplication factor. ex- ?*4 = 28 and 25*4 = 100 *Since 25*4 = 100, find what number times 4 equals 28* Step 3: Find the numerator. ex- 7/25 = 28/100 *Since 4*7 = 28, 28% of 25 = 7 Example B, Step 1: Write the percent as a fraction. ex-35% of 60 = 35/100 of 60 Step 2: Multiply. ex- 35/100 of 60 = 35/100x60=2100/100=21 *Simplify* Example C, Step 1: Write the percent as a decimal. ex- 5% = 5/100 = 0.05 Step 2: Multiply. ex- 180 * 0.05 = 9, 5% of 180 is 9.