APMJUNE 14

DIR SIR I have Q in JUNE 14, for Q1. The part (iii), when calculate the EVA. my workings are: operating profit: 10852970 less: (10852970*25%) (2713243) Add: marketing 3819000 Less: tax paid in cash (2100000) TOTAL 9858727 I REMEMBERED this method of calculating EVA was in the lecture, and I calculate it based on our method. however, in the examiner answer, the examiner use the finance cost * interest rate to be deducted amount, in our lecture we should use the PBIT *tax rate. what's wrong with my answer? thanks sir