How to find duplicate entries, and delete the earlier modified entry?

Hi everyone,

I have a problem with duplicate removing.

My WorkbookA currently copies one whole workbook from an external spreadsheet and copies it into a new sheet.

My code currently uses a duplicate removal method via sorting. This means after sorting the copied data, the code will leave behind the entry with the lowest price and delete others.

For e.g.
Hello $0.02
Hello $0.03
Hello $0.04

After running, the code will leave only:
Hello $0.02

Right now, my colleague is asking me if it is possible to find out which duplicate entries are modified latest, and delete the earlier modified entry.

For me, the trouble is:
1) I don't know how to sort by modified date/time, if it is possible at all.
2) The data I am sorting is copied over from another workbook into WorkbookA. So I guess all the date/time records are erased?

Thanks in advance!