A doctor asked 200 people over the age of 50 whether they suffered from depression or heart disease. The results were 16 suffered from depression, 28 suffered from heart disease and 24 suffered from both. In a group of 5000 people over the age of 50, how many people would the doctor except to suffer from heart disease?
Are you asking for just the people with ONLY heart disease? If so, that means the doctor record 28 people out of 200 suffered from heart disease. That's 14%. Multiply 5000 by .14 and you would get 700 people are expected to suffer from heart diseases.
If not, I'm guessing you would have to include the people that suffers from both as well. That's 52 out of 200, which is 26%. Multiply 5000 by .26 and you get 1300 people.