The most frequent type of adverse reaction occurring with ibuprofen is gastrointestinal. In controlled clinical trials, the percentage of patients reporting one or more gastrointestinal complaints was $.$ Assume the probability that a randomly selected patient will suffer a gastrointestinal side effect after taking ibuprofen is $($Assume independence$).$ A medical researcher randomly selects $4$ migraine patients and prescribed ibuprofen

$1.$ Suppose the medical researcher had a large group of migraine patients. How many patients on average would need to be selected before finding someone who will suffer a gastrointestinal side effect after taking ibuprofen? $($Hint: E$($x$)=1/$p$)$