In 2011, the number of text messages sent and received by teenage girls (ages 12 - 18) was strongly right skewed.The mean number of messages sent and received each day was 165 with a standard deviation of 45 messages.Suppose we assume teenage boys (ages 12 - 18) send and receive the same number of messages daily.

1. Completely describe the sampling distribution of the sample mean number of text messages sent and received when samples of 253 teenage boys are selected.

• mean:
• y
• y
• =
• standard deviation:
• y
• y
• =(round your answer to 4 decimal places)
• shape: the distribution of
• y
• y
• isSelect an answer
• not normally distributed
• normally distributed
• becauseSelect an answer
• the population of number of text messages sent is normally distributed
• the sample size is not large
• the population of number of text messages sent is not normally distributed
• the sample size is large

1. Using the distribution described in part a, what is the probability of observing a sample mean of 161.696 or less?

• z =(round to 2 decimal places)
• probability =(include 4 decimal places)

1. Classify the probability found in part b using the rule of thumb discussed in class.

• The probability would be classified as small.
• The probability would be classified as large.

1. Based on the probability found, what conclusion can be reached?

• ThereSelect an answer
• is not
• is
• sufficient evidence to conclude the mean number of text messages sent by male teenagers isSelect an answer
• greater than
• less than
• 165.