Well, if 25 apples is $15, then the equation is 15/25. Divide by 5/5 (which is another way of saying 1). You get 3/5. So now, you know that for $3 you get 5 apples. now to get the price of one apple, you must multiply both $3 and 5 by 1/5 so that you will get the price of one apple. One apple is $0.60. To get the price of 3 apples, just multiply $0.60 by 3 which gives you $1.80.
