Percentages are usually found by taking the value that you want to find and dividing it by the whole amount (100% of the total value available). In this case, getting 100% on the test would mean getting 120/120, because 120 points is 100% of the points available. However, the student only got 96 points out of the whole 120 points, so to find the percentage, you do 96/120 to find what part of 96 comes out of 120. Then to convert to percentage, multiply that value by 100 to get your finale value.
Let the measure of the complementary angle be x so that the measure of the other angle is 14x. The total measure of the angles is 180 degrees. Thus, one angle measures 12 degrees. The other angle measures 14*12=168 degrees.
