Ah yes. Let's all go back to kindergarten and we'll relearn about color shall we?
Yellow + Red mixed together makes Orange
Printing basics
KCMY (Black, Cyan, Magenta And Yellow)
Each printing plate is made up these 4 colors (4 Color Press).
Then background is made to look bright red, in order to make bright red, you need to add yellow to the magenta (red) because magenta is more of a pinkish color when printed on paper.
As the press is running, the press operator adds each color from a console by pushing the keys (buttons) for each area of the book. When the desired color is achieved or close to it, they start saving the product.
Since either the ink in the fountian is controlled by a sensor when it starts getting low, it refills automatically from an ink leveler or by hand. When either the ink leveler eye isn't working properly, the ink will run low causing the red ink to fade away and since yellow and red makes orange, more yellow is exposed underneath the magenta, making your NM 87 appear more orange than the bright red it should be. The press operator should have had those books thrown out but either he doesn't care, missed it or is so concerned about his waste count, he saved them away and out the door they went and now threads are created asking "Why does my comic look like this"??
Now you know, and knowing is half the battle!!
G.I Joe!!