The ratio of the number of text messages sent by Robert to the number of text messages sent by his sister, Jenny, is 3 to 5. Together they sent a total of 48 text messages.

Now, martin can reasonably guess that the standard deviation for the entire population of people at the mall during the time of the survey is $1.50. what is the 95% confidence interval about the sample mean? interpret what this means in the context of the situation where 95 people were surveyed and the sample mean is $8. use the information in this resource to construct the confidence interval.