I was just wondering if it's possible to have different file sizes in different operating systems. Ubuntu shows 47.5gb while Windows was showing 44.2gb. I don't know but I checked each and every file. Nothing is missing but still different sizes. How?
It's simply an issue of different units. Windows uses binary prefixes (1024 bytes = 1 kibibyte (KiB), 1024 kibibytes = 1 mebibyte (MiB) etc.) whereas Ubuntu in general uses the metric prefixes (1000 bytes = 1 kilobyte (KB), 1000 kilobytes = 1 megabyte (MB) etc.). Windows also uses "GB" instead of "GiB" and so on.
Thus 44.2 GB in Windows = 44.2 GiB = 44.2×1.024³ GB ≈ 47.4594 GB ≈ 47.5 GB (in Ubuntu), so it adds up.