Ad Display Strategies in Newsfeed

Consider two strategies for displaying advertisements within a Newsfeed: 1. One ad is shown for every 25 stories. 2. Each story has a 4% probability of being an ad. Calculate the expected number of ads displayed in a sequence of 100 news stories for each strategy. Additionally, if the second strategy is chosen, what is the probability that a user sees exactly one ad in 100 stories?

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