RIR how many pullets?

[cedge]

They all run around very good let them out and they walk around I've bought some some electrolytes to mix with their water. They don't seem as well as my slws the slws are are for sure 10 weeks I got them at 3 days they are bigger and when they walk they move their heads like a chicken should but the others don't do that I thought it was the breed any suggestions on what I should do for the other 4? I got them from different breeders he said they were 7 weeks when I got them