Answer:
Average atomic mass of copper is 63.545642 amu
Explanation:
100 atoms of copper contains 69.17 number of [tex]Cu_{29}^{63}[/tex] atoms and 30.83 number of [tex]Cu_{29}^{65}[/tex] atoms.
Therefore average atomic mass of copper is given by-
[tex]\frac{(69.17\times atomic mass of Cu_{29}^{63})+(30.83\times atomic mass of Cu_{29}^{65})}{100}[/tex]
=[tex]\frac{(69.17\times 62.929599 amu)+(30.83\times 64.927793 amu)}{100}[/tex]
=63.545642 amu