How do you get the pendants red?

If you are using paint then you would just get a big blob of red paint. Or if you are using pencil crayons then it would just look like red. It would look like a solid colour. Or if you are using...

Two, two, two. Or 22 times 102 ohms, or 2200 ohms, or 2.2K ohms, or just 2.2K, as in, "I've got a 2.2K resistor that needs replacing. It's a quarter watt."

An object is red because it is absorbing the blue end of the visible spectrum (higher frequencies) and reflecting back the red (lower frequencies) to your eyes.

You're reading it backwards, I think. A red, red, red, gold resistor is 2.2K, 5% tolerance.

The same reason why red roses appear red, or anything else appears red for that matter. Objects appear red when they absorb all other colours of light (remember, light from the sun is a spectrum of...