I installed linux mint 15 and Ubuntu 13.04 on separate partitions, all under one extended partition (sda3). Linux mint was installed first, so it ended up on sda5. linux-swap is sda6, and ubuntu is on sda7. I decided I liked ubuntu better, so to regain space, I want to delete the partition with linux mint and let the ubuntu partition fill in the free space. I tried using gparted to delete sda5, but it gave me the message "Please unmount any logical partitions having a number higher than 5". Well, none of the partitions are even mounted except sda7, because ubuntu is running off of it (it says mount point is /). I tried unmounting it anyway and it gave me the message "The partition could not be unmounted from the following mount points:


Most likely other partitions are also mounted on these mount points. You are advised to unmount them manually."
Now what do I do? I just need to get rid of sda5 to free up space.