I had downloaded macOS Sierra(~4.88GB) from App Store to create a bootable for a friend on my Macbook Air. After doing that successfully, I deleted the macOS Sierra Installer app from Applications directory. But my Drive size was not freed by 4.88GBs instead deleting it freed only 1GB. Are there any residual files I need to remove manually?
The problem is with a disk image with the name Apple RID... created by the macOS Sierra installer which did not get ejected when macOS installer was deleted and was occupying around 5.5GBs and wasn't visible anywhere except in Disk Utility.
After ejecting that disk using Disk Utility and restarting the laptop, the memory which was held up got freed.