A shopper spends $25 to purchase floppy disks at 50¢ each. The next ... ...

A shopper spends $25 to purchase floppy disks at 50¢ each. The next day, the disks go on sale for 30¢ each and the shopper spends $45 to purchase more disks. What was the average price per disk purchased?
(A)    25¢
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Nova Math - Problem Set Q: Averages