Answer:
There was a 50 percent increase in price
Explanation:
To get the percentage increase in price, we will have to apply this formula:
(New price - original price)/ (Original price) X 100
From our question, we have that new price = $9
Original price = $6
Percentage change in price =

Hence, this means that there was a 50 percent increase in price if a CD bought for $6 was sold for $9