Answer:
9
Explanation:
(just for confirmation)
For 11 shelves, 8 CDs each = 11 x 8 = 88 CDs in total
Amd rest shelves have only 6 CDs
So, for us to know, = the CDs left = total - no. Of cds
= 142 - 88 = 54
So the no. Of shelves = 54/6 ( bc we need to know the no. Of shelves)
So 54/6 = 9.
So 9 shelves