Adding one chick?

[speckledegg]

Would you or is it possible to add 1, 5 week old chick to a flock of 3, 10 week old chicks? I'm concerned the age difference would be too large and I'm worried about just adding 1. Has anyone successfully done this? I probably won't quarantine as the 5 week old will be coming from the same place I got my 10 week olds and hasn't been outside yet.

Thanks!