A poster advertising a student election candidate is too large according to the election rules. The candidate is told she must reduce the length and width of the posted by 20.0%. By what percentage must the area of the poster be reduced?
If the original length and width are x and y, the original area is xy. If each was reduced by 20%, you would have .8x and .8y , multiply those and the area is .64xy, which means that the area is reduced by 36%