Nick buys 3 postcards during each day of vacation. Write an equation that shows the relationship between the days of vacation x and the number of postcards bought y. Write your answer as an equation with y first, followed by an equals sign.

Need this asap if anyone can i would be very grateful. if you could show workings that would really

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

How can you tell when x and y are not directly proportional?