How many MB are there in 1GB?

1000 X 1.8 = 1800 Mb (using conventional meaning of Giga, which is what hard drive manufacturers use in order to sell you less than advertised using the correct computer notation below)

1024x1.8 = 1843.2 MB is the correct answer using base 2 which is what most computer manufacturers use (1 GB of memory is 2^10 or 1024 MB of memory).