How do I interpret constants of proportionality

Solve the problem by making up an equation. a child is 12 years old, and his father is 32 years older. in how many years will the age of the father be 3 times the age of the child?

What is the solution of the systems of equations? y=2/3x+3 x=-2

Abag contains 4 red, 7 blue and 5 yellow marbles. event a is defined as drawing a yellow marble on the first draw and event b is defined as drawing a blue marble on the second draw. if two marbles are drawn from the bag, one after the other and not replaced, what is p(b|a) expressed in simplest form? a. 7/16 b. 7/15 c. 14/16 d. 14/15