So here is the answer. Normally, 10 people have 20 legs since each person has 2 legs each. But given the scenario that two people don't have legs, this would mean 20 minus 4, is 16 legs. Then one person has 3 legs, 16 plus 3 and it is 19. And then, another person has one leg, 19 plus 1 is 20. Therefore, the total legs would still be 20. Hope this helps. The dog does not count.