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Jayce is testing the effectiveness of a cell phone case made out of a new type of recycled plastic. He randomly samples $20$ cases from every batch of $1,000$ manufactured and tests their effectiveness at protecting a phone dropped from a set height. Here are the data from one sample. $\newline$--------------------------------------------- ---------$\newline$Test result Frequency$\newline$Highly effective (no damage to case or phone) $9$$\newline$Moderately effective (damage to case only) $10$$\newline$Ineffective (damage to case and phone) $1$$\newline$--------------------------------------------- ---------$\newline$What percentage of the cases in this sample are rated as moderately or highly effective?$\newline$____$\%$