Question

A poll of 72 seniors, taken three weeks before the selection of the school
Homecoming Queen, identified 60 who planned to vote for Jenny Wonderful.
Unfortunately, a week after the poll was taken, the school newspaper ran an
article that quoted Jenny slandering her opponents. Another poll of 80 seniors
taken shortly after the article appeared showed that 56 planned to vote for
Jenny. Does this indicate a significant drop in support for Jenny? Use good
statistical reasoning to support your answer.

Answer 1

For us to determine if indeed there was a significant drop in the number of supporters, we take the percentages that Jenny got in each survey. 

First survey: (60 / 72) x 100% = 83.33%
Second Survey: (56 / 80) x 100% = 70%

A drop of 13.33% in the percentage vote might be significant for Jenny. Thus statistically, there was a significant drop in the number of supporters.