Answer:
12:7
Step-by-step explanation:
The question asks for the ratio of red to blue. So first you identify how many red markers there are. In this case there are 12. Then the problem asks for blue markers. In this problem there are 7. The problem also asks for red to blue. So you put the red value first which is 12 and the blue value second which is 7. That's how you get 12:7
