Service Tax Calculation (For Transporter)

Hi

We have a requirement related with Service Tax Code , related with Transport Vendor where in Clinet wanst the Service Tax as 10.3% on 40% of the Invoice.

For example: say the Invoice Value is Rs. 100. The Client want Service Tax 10.3% on Rs 40 i.e. Rs. 4.12

Pls. guide.

Regards,