Q:

How to get average of Arun's weight? 

This is an aptitude problem I found in a website, question no 9:

In Arun's opinion, his weight is greater than 65 kg but less than 72 kg.  His brother does not agree with Arun and he thinks that Arun's weight is greater than 60 kg but less than 70 kg.  His mother's view is that his weight cannot be greater than 68 kg.  If all are them are correct in their estimation, what is the average of different probable weights of Arun? 

How can I solve this?  Actually I am getting more confused at different probable weights.  What is it meaning? 

A:

If all are correct, then Arun's weight can not be greater than 68 Kg and can not be less than 66 Kg.  Thus average is 67 Kg.