Exchange gain or loss ??

have problem in the import purchases: Suppose I paid $5000 @ 45.15 on 25/5/2009 in advance for purchases of material which cost me $25000, I received the material on 30/6/2009, I paid balance amt on 25/6/2009 @ 47.20. On import doc. there is specifically indicate tht it is D/P transaction.so at the time of passing the entry rate will have to taken as per BOE for whole $25000 or $25000 @ 47.20

I'm PCC student , I want to clear my concept !!

pls help me.my email id