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<?php $data1 = array("Peter" => "1", "Ann" => "1", "Susan" => "2", "Tom"=> "3", "John" => 3, "Jenny" => 3); $counts =array_count_values($data1); rsort($counts); $find = $counts[0]; Var_dump(array_keys(array_intersect($data1, [$find])));

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