Question

according to a study by nielsen mobile, \teenagers 13 to 17 are by far the most prolific texters, sending 1742 messages a month.\ mr. williams, a high school statistics teacher, was skeptical about the claims in the article. so he collected data from his first - period statistics class on the number of text messages they had sent over the past 24 hours. here are the data. 0, 7, 1, 29, 25, 8, 5, 1, 25, 98, 9, 0, 26, 8, 118, 72, 0, 92, 52, 14, 3, 3, 44, 5, 42 alejandro, who sent 92 texts, has a standardized score of z = 1.89. what is the correct interpretation of alejandros z - score? to calculate this value, take alejandros number of text messages, subtract the class average, and then divide by the standard deviation. alejandro sent 1.89 more text messages than average. alejandros text messages outnumbered his classmates by a factor of 1.89. the number of texts sent by alejandro is 1.89 standard deviations above the mean number of texts sent by the students in the sample.

Explanation:

The z - score represents the number of standard deviations a data - point is from the mean. A positive z - score indicates the data - point is above the mean. Here, Alejandro's z - score of 1.89 means his number of text messages is 1.89 standard deviations above the mean number of texts sent by the students in the sample.

Answer:

The number of texts sent by Alejandro is 1.89 standard deviations above the mean number of texts sent by the students in the sample.