Fact: Asthma, a bronchial condition, is much less common ailment than hay fever, an allergic inflammation of the nasal passages.Fact: Over 95 percent of people who have asthma also suffer from hay fever.
If the information given as facts above is true, which of the following must also be true?
画两个韦恩图,Asthma的圈圈要比hay fever的圈圈小, 两个圈圈重叠部分就是‘Over 95 percent of people who have asthma also suffer from hay fever’,但是对于A 来说的95%必然对HF来说要小于95%,后者的圈圈大,重叠部分占到它整个的比例小