Is x% y and y% of x always, sometimes or never equivalent?

Which equation requires the division property of equality to be solved?

Rewrite the following quadratic functions in intercept or factored form. show your work. f(x) = 3x^2 - 12

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?