A research team studied the rate at which infants in the three different countries vocalized distress. Below are the scores from each country. Which group of infants showed the highest mean rate of distress vocalization over the 45-minute observation period? Country A: 9, 9, 10, 13, 8, 8, 11, 11, 10, 7, 13, 6, 18, 9, 9, 12, 13, 10, 5, 14
Country B: 15, 15, 16, 19, 14, 14, 17, 17, 16, 13, 19, 12, 18, 10, 10, 15, 15, 2, 2, 5
Country C: 4, 6, 20, 17, 15, 30, 18, 18, 25, 2, 29, 17, 16, 35, 19, 1, 30, 25, 16, 15
A)Country A
B)Country B
C)Country C
D)Countries B and C were equal

Question

Quizplus · Accepted Answer

To find the highest mean rate of distress vocalization, we need to calculate the mean of each country's scores. 
Country A: Mean = 10.45 
Country B: Mean = 13.7 
Country C: Mean = 18.3 
Thus, the group of infants that showed the highest mean rate of distress vocalization over the 45-minute observation period was Country C.

A Research Team Studied the Rate at Which Infants in the Three