Analysis of a metallic meteorite sample reveals a novel element, Z, which exists as two stable isotopes.
The table below shows the mass numbers and percentage abundances of these two isotopes in the meteoritic sample.
| Mass number | Percentage abundance (%) |
|---|---|
| 121 | 57.3 |
| 123 | 42.7 |
Calculate the relative atomic mass (ArA_rAr) of element Z in this sample.
Give your answer to 1 decimal place.