if the relative atomic mass of natural copper is 63.54,calculate the proportions of the isotope 65cu and 63cu

Answer 1

63x + 65(1-x) = 63.54
x = .73

so, 73% 63Cu and 27% 65Cu

Answer 2

How did you arrive at x=.73
Please break the formula

Answer 3

The answer to that question is this: 63.54 - 63 =0.54
65 - 63.54 = 1.46
0.54+1.46=2
0.54÷2 ×100= 27%
1.46÷2 ×100= 73%
And that's final.

Answer 4

How do we arrive to 73%when the proton number is not included only the mass number is there so explain to me because I don't understand why the proton number is not included may be this is not the question