here we have page size of 4Kb so 12 bits are needed to represent a single word.
Now number of pages are 2^48 / 2^12 = 2^36 pages are possible
So 36 bits from address refer to page number and remaining 12 bits refer the Word within that page ..
Now address is 48 bits so first 36 bits are 304F48AC5 (each one is 4 bits as its 16 bit )...which is a page number
and remaining 12 bits are 345(again 4 bits each ) which is word offset that is required word number within given page number