var yourVariable = StatisticFormula.InverseFDistribution(param1, param2, param3)
var chart = new Chart();
var value = chart.DataManipulator.Statistics.InverseFDistribution(0.05, 15, 30);
var statisticFormula =
(StatisticFormula) typeof(StatisticFormula).GetConstructor(
BindingFlags.NonPublic | BindingFlags.Instance,
null, Type.EmptyTypes, null).Invoke(null);