Let N be the number of dogs with 4 legs Carly worked on.
All the dogs with 4 legs had 4N paws.
There were 3 * 3 = <<3*3=9>>9 paws on dogs with 3 legs.
At 4 nails per paw, she trimmed 164 / 4 = <<164/4=41>>41 paws.
She worked on 4N + 9 = 41 paws.
Thus, she worked on 4N = 32 paws on dogs with 4 legs.
She worked on N = 32 / 4 = <<32/4=8>>8 dogs with 4 legs.
Thus, Carly worked on 8 + 3 = <<8+3=11>>11 dogs.
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