Mohan , i think the 375 u r , talking abou the H.T side and amps 1100 u r talking about in the L/T side. Anyway it can be solved by the basic power P=VI cos of Phi formula. calculate it from one side , either HT or LT side find the amps and do the basic math. voltage u , know it , p.f u know it then find the p value and u can conver it by th basic formula and convert it in KVA