Untitled

include <bits/stdc++.h>
using namespace std;
#define int long long
int f(int n, int k, int g)
{
    int y;
    if (g % 2 == 0)
        y = g / 2 - 1;
    else
        y = g / 2;
    if (n * y >= k * g)
        return k * g;
    else
    {
        int x = (n - 1) * y;
        int u = k * g - (n - 1) * y;
        if ((u % g) >= ceil(g / 2.0))
            x -= g - (u % g);
        else
            x += u % g;
        return x;
    }
}
int32_t main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int t;
    cin >> t;
    while (t--)
    {
        int n, k, g;
        cin >> n >> k >> g;
        cout << f(n, k, g) << '\n';
    }

    return 0;
}