There are 6 multiples of 8 below 50. 8, 16, 24, 32, 40, 48. There is a 44/50 chance that he doesn't choose 8 the first time. The second time is also a 44/50 chance he doesn't choose 8. so the probability that he doesn't choose at least 1 multiple of 8 is (44/50)^2=0.7744. so the probability that he chooses at least 1 multiple of 8 is 1-0.7744=\(\boxed{0.2256}\)

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