1amu = 931 Mev .......how do we prove this?

we have

1 amu = 1.660 X 10^{- 27} kg = 1.492 X 10^-10 J  ( using mass- energy equivalence)

and

1 MeV = 1.602 X 10^-13 J

so,

1 amu = 1.492 X 10^-10/ 1.602 X 10^-13 MeV

or

1 amu  = 931.49 MeV