To convert a distance of 4500 yards to miles, which ratio could you multiply by?

Pls! does anybody know a shortcut for answering these types of questions in the future?

Mexico city, mexico, is the world's second largest metropolis and is also one of its fastest-growing cities with a projected growth rate of 3.2% per year. its population in 1991 was 20,899,000 people. use the formula p = 20.899e0.032t to predict its population p in millions with t equal to the number of years after 1991. what is the predicted population to the nearest thousand of mexico city for the year 2010?

Factor the expression using gcf 9b+45