A public health researcher examines the medical records of a large sample of men who died in 1999. Of this sample, she finds that 22.4% died with heart disease. Further, she finds that one third of the men in the sample had at least one parent with heart disease, and of this latter group, 32.7% died of heart disease.
What percentage of men in the sample died of heart disease and neither parent had heart disease?

Question

A public health researcher examines the medical records of a large sample of men who died in 1999.  Of this sample, she finds that 22.4% died with heart disease.  Further, she finds that one third of the men in the sample had at least one parent with heart disease, and of this latter group, 32.7% died of heart disease.
What percentage of men in the sample died of heart disease and neither parent had heart disease?