How can I add this unallocated space to my partition?
I am using Gparted when booting from a Ubuntu 15.10 CD
I have 74.99 GB unallocated storage. I want to add that storage to my ext4 partition (/dev/sda5)
However, when I try to click resize on ext4, I get a maximum size of it that is not much more than its current size. I. e. the GUI shows a maximum size limit just around 28 GB and I don't know how to actually add the 74.99 GB.
Advice appreciated.
/dev/sda4
is a "container" for the logical partitions 5 and 6, so you need to resize it first. (The reason you can't resize 5 is that it must stay inside 4.)