• The relative atomic mass of each element is calculated from the?mass number?and?relative abundances?of all the isotopes of a particular element
• The steps below are to calculate the relative atomic mass
• Start by finding out the mass of 100 atoms, then divide the result by 100 to get the Ar

• The top line of the equation can be extended to include the number of different isotopes of a particular element present, so, if there were 3 isotopes present then the top line of the equation would read:

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Answer

Relative Atomic Mass = 85.6