At what rate service tax is to be charged on money received as cancellation charges,if the service provider paying ST on abatement basis.For Eg: if it is a tour operator providing package tour levied tax (25%*10.3%)(F Y 2010-11)) ie 75% of value is not taxable.Suppose money received 100000 and by the fault of customer ,tour was cancelled,so the tour operator deducted 50000 as cancellation charges. then what is the amount of service tax to be paid to the credit of Govt.