public static boolean checkBoth(int[] vals) {
    boolean gt15 = false;
    boolean lt10 = false;

    for (int i = 0; i < vals.length; i++)
        if (vals[i] > 15)
            gt15 = true;


    for (int i = 0; i < vals.length; i++)
        if (vals[i] < 10)
            lt10 = true;


    return gt15 && lt10;
}