/*
* ДЗ 3 Задача "Ссуда"
*/
void getProcent() {
    double s, m, left, right, middle;
    int n;
    left = 0;
    middle = 50;
    right = 100;
    cin >> s >> m >> n;
    while (s * (middle/100) * pow(1 + (middle / 100), n) / (12 * (pow(1 + (middle / 100), n) - 1)) != m) {
        if (s * (middle / 100) * pow(1 + (middle / 100), n) / (12 * (pow(1 + (middle / 100), n) - 1)) > m) {
            right = middle;
            middle = (left + middle) / 2;
        }
        else if (s * (middle / 100) * pow(1 + (middle / 100), n) / (12 * (pow(1 + (middle / 100), n) - 1)) < m) {
            left = middle;
            middle = (middle + right) / 2;
        }
    }
    cout << middle;
}