Inequalities Questions

In Karthik's opinion, his weight is greater than $55\text{kg}$ but less than $62\text{kg}$. His father does not agree with Karthik, and he thinks that Karthik's weight is greater than $50\text{kg}$ but less than $60\text{kg}$. His sister's view is that his weight cannot be greater than $58\text{kg}$. If all are correct in their estimation, what is the average of the different possible weights of Karthik?