Hannah's AdBlock blocks all but 20% of ads, and 20% of the ads it doesn't block are actually interesting. What percentage of ads aren't interested and don't get blocked?
First find the percentage of ads that aren't interesting: 100% - 20% = 80%
Then multiply that percentage by the percentage of ads that don't get blocked to find the percentage of ads that meet both criteria: 80% * 20% = 16%
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