You enjoy bargain hunting at garage sales. From experience you know that at any random garage sale there isa 30% chance of finding a useful item. From experience, you know that at any random garage sale there is a 40% chance of finding a useful piece of furniture. Experience has also taught you there isan 80% chance of not finding a useful item or not findinga useful piece of furniture. Given that you find a useful piece of furniture at a garage sale, what is the probability you do not find a useful item at that same garage sale