Question 1. I am assuming you meant 9/16, and in that case, the answer would be 0.5625. 9-16 is -7.
Question 2. 35.7% in decimal form is relative to what the percent is of. 35.7% of a million is different than 35.7% of one.
Question 3. Once again, this is relative as to what. Percentage of the weight of an elephant? It is important to specify in these types of equations.