The relative atomic mass of element A : 6.075 u
Further explanation
The elements in nature have several types of isotopes
Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.
So Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.%
...
Element A
mass number of isotope 1 = 6 , percent : 92.5%
mass number of isotope 2 = 7, percent : 7.5
Relative atomic mass of element A
[tex]\tt = 92.5\%\times 6+7.5\%\times 7\\\\=5.55+0.525=6.075~u[/tex]
