You can put this solution on YOUR website! Don't know. You should ask at Kinko's
Your problem doesn't really give enough info.
But we can make a bunch of assumptions.
3 in by 5 in is not a poster but an index card same as a picture postcard.
Perhaps you mean feet and not inches.
3*5=15 square inches
6*10=60 square inches which is 4 times the postcard
So it should cost 4 times as much.
6 by 10 is just a large postcard not a poster either.
4*6.50=$26.00 for a large postcard
