The above is not quite right, but good effort Loosehead and C-C.
Interest from loans are usually (not allways) calculated on an APR (Annual Percentage Rate). If the 6.5% above is APR that rate only relates to a period of 1 year (or 52 weeks or 365 days).
The formula for calculating interest for periods above or below is as follows:-
(1+i)^n-1 where i = interest & n = time
6/52 = 0.1153846 (n)
therefore
(1 + 0.065)^0.1153846 - 1 = 0.0072928 or 0.72928%
�27,000 x 0.72928% = �196.91 (or thereabouts)