Answer pls asap julie has a bag containing p blue marbles and q red marbles. the ratio of blue to red is 2: 3. she adds r blue marbles. the ratio of blue marbles to red marbles is now 2: 1. what is the ratio between p and r?

Lets say for arguments sake that the bag contained  2 blue and 3 red marbles

p:q = 2:3 In order  to get a ratio of 2:1 we would have to add 4  blue  marbles

(6:3 = 2:1).

So the ratio p to r =  2:4  = 1:2  answer.

step-by-step explanation:

(3rd option) - c