if a, b, c, and d are positive numbers and a/b < c/d , which of the following must be true? I. (a+c) / (b+d) < c/ d II. (a+c) / (b+d) < a/b III. (a+c) / (b+d) < a/b + c/d a) none b) I only c) II only d) I and II e) I and III OA: B how do you solve this problem? I believe III. was an equ...