SOLUTION: John surveyed a group of people about their knowledge of rats. To the nearest tenth of a percent, he found that 86.8% of the people surveyed thought rats carried diseases. Of the

Algebra ->  Percentages: Solvers, Trainers, Word Problems and pie charts -> SOLUTION: John surveyed a group of people about their knowledge of rats. To the nearest tenth of a percent, he found that 86.8% of the people surveyed thought rats carried diseases. Of the       Log On


   

Question 33324: John surveyed a group of people about their knowledge of rats. To the nearest tenth of a percent, he found that 86.8% of the people surveyed thought rats
carried diseases. Of the people who thought rats carried diseases,45.7% said that rats frequently carried rabies. Since rats do not frequently carry rabies these 21 people were mistaken. HOw many total people did john survey?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Let number of people surveyed be "x".
Then # who thought rats carried deseases = 0.86x
And 0.457(0.86) said rats frequently carried rabies
EQUATION:
number who thought rats frequently carried rabies = 21
0.457(0.86x)=21
x= 53.43...
Number of people surveyed was 54
Cheers,
Stan H.