The three stable isotopes of neon :$Ne^{20}, Ne^{21},Ne^{22}$ have respective abundances of $90 .51 \%, 0.27\%$ and $9.22\%$ . The atomic masses of three isotopes are $19.99$ amu , $20.99\;amu$ and $21.99\;amu$ Obtain the average atomic mass of neon .

Question

$\begin{array}{1 1} 19.45 \;amu \\ 19.54\;amu \\ 20.45\;amu \\ 20.54\;amu \end{array} $