import java.util.*;
import java.io.*;
 
public class Main {
 
    public static void main(String[] args) throws IOException {
        BufferedReader load = new BufferedReader(new InputStreamReader(System.in));
        int t = Integer.parseInt(load.readLine()) ;                // number of tests 1-1000
        for (int i = 0; i < t; i++) {
            String[] temp = load.readLine().split(" ");
            int[] tabInt = Arrays.stream(temp).mapToInt(Integer::parseInt).toArray();
            float result = (float) ( (2 * tabInt[0] * tabInt[1]) / (tabInt[0] + tabInt[1]) );
            System.out.println((int) result);
        }
    }
}
 

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Mgo1MCA2MAo3MCA0MA==

2
50 60
70 40