Question

In a study of towns, there was a positive correlation between the number of mail boxes and the number of traffic lights in a town. Which variable is most likely the lurking variable that explains the correlation?
A . Population

B. Commute times

C. Ages of residents

D. Highest temperatures

Answer 1

1. 25 + 3u = 2u
           -3u = -3u
    25 = -u
    -25=u
2. 14x - 8 = 6x
    8x - 8 = 0
    8x = 8
    x=1
3. 8.5 - 3z = -8z
    8.5 = -5z
    -1.7 = z
4. 9m + 14 = 2m
    7m + 14 = 0
    7m = -14
    m = -2

Answer 2

The answer is A, population. If there are more people, it means there will be more mail boxes and a higher need for traffic lights.