In a survey concerning the smoking habits of consumer it was found that 55% smoke cigarette A, 50% smoke cigarette B, 40% smoke cigarette C...

In a survey concerning the smoking habits of consumer it was found that 55% smoke cigarette A, 50% smoke cigarette B, 40% smoke cigarette C, 30% smoke cigarettes A and B, 20% smoke cigarettes A and C, 12% smoke cigarettes B and C only 10% all three cigarettes. What percentage of the population did not smoke?