I install ubuntu on a 24GB partition on my MB Air running Sierra the other day. I've since erased the partition (from within ubuntu) but Disk Utility no longer recognizes the partition. Basically the 24GB is useless to me, I believe the term is unallocated, and I'd like to add it back to my main Macintosh HD. From what I've read I should wipe the entire disk clean, reinstall macOS, and restore all my files from Time Machine. I'm willing to do this but would rather take an easier route. Is there a faster way to accomplish this?