There is an issue with treatment side effects: individuals with a certain variant of the (fictitous) CEHS gene suffer serious muscle cramps at a rate of 2.1 per month, while those without the variant suffer cramps at a much lower 0.8 per month. 9% of the population have this gene variant. If an individual suffers a third cramp before the end of two months, what is the probability that he/she has the variant form of the gene?