76 The attention span of a two year old is exponentially distributed with a mean of about eight minutes Suppose we randomly survey 60 two year olds a In words X b X c In words X d X e Before doing any calculations which do you think will be higher Explain why i The probability that an individual attention span is less than 10 minutes ii The probability that the average attention span for the 60 children is less than 10 minutes f Calculate the probabilities in part e g Explain why the distribution for X is not exponential