#include <cstdio>

int n;
int A[11000],B[11000];

double getV(double r,double h) {
    return r * r * h / 6.0;
}

double getS(double H) {
    double S = 0.0;
    for(int i=0;i<n;++i) if( (double)A[i] > H ) {
        double h = A[i] - H;
        double r = h * ( (double)B[i]/(double)A[i] );
        S += getV(r,h);
    }
    return S;
}

int main() {
    int T;
    scanf("%d",&T);
    while( T-- ) {
        int mx = 0;
        double V = 0.0;
        scanf("%d",&n);
        for(int i=0;i<n;++i) scanf("%d",&A[i]);
        for(int i=0;i<n;++i) scanf("%d",&B[i]);
        for(int i=0;i<n;++i) {
            if( A[i] > mx ) mx = A[i];
            V += getV(B[i],A[i]);
        }
        double l = 0.0,r = mx;
        while( r-l > 0.001 ) {
            double m = (l+r)/2;
            //printf(">> %.4lf :: %.4lf\n",getS(m)/V,m);
            if( getS(m) > (V/2.0) )
                l = m;
            else
                r = m;
        }
        //fprintf(stderr,"%.3lf\n",(l+r)/2);
        printf("%d\n",(int)((l+r)/2));
    }
    return 0;
}