public static class CoinHelper
{
    public static float Format(int coins)
    {
        int whole = coins / 4;
        int fraction = coins % 4;
        return float.Parse(whole + "." + fraction);
    }

    public static int RcToCoins(float coins){
        string s = coins.ToString("N1");
        int whole = int.Parse(s.Split('.')[0]);
        int fraction = int.Parse(s.Split('.')[1]);
        return (whole * 4) + fraction;
    }

    public static string FormatString(int coins)
    {
        return Format(coins).ToString("N1");
    }
}