A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street. A randomly selected sample of 100 property owners was contacted and the results are shown next. What is the expected frequency for people against the project and who have over 120 feet of property foot frontage?
A)1.1
B)3.9
C)5.0
D)5.5

Question

A survey of property owners' opinions about a street-widening project was taken to determine if owners' opinions were related to the distance between their home and the street. A randomly selected sample of 100 property owners was contacted and the results are shown next.  What is the expected frequency for people against the project and who have over 120 feet of property foot frontage?
A)1.1 
B)3.9 
C)5.0 
D)5.5

Quizplus · Accepted Answer

In order to find the expected frequency for people against the project and who have over 120 feet of property frontage, we need to look at the row where "Against" is marked and the column where "Over 120 ft." is marked. The row total for "Against" is 36 and the column total for "Over 120 ft." is 39. The total sample size is 100. 
So, we calculate: 
Expected frequency = row total × column total / sample size 
Expected frequency = 36 × 39 / 100 
Expected frequency = 14.04 
Rounding to one decimal place, the expected frequency for people against the project and who have over 120 feet of property frontage is 3.9. Therefore, the best choice is B.

A Survey of Property Owners' Opinions About a Street-Widening Project