An unknown element Q has two known isotopes: 60Q and 63Q. If the average atomic mass is 60.5 amu, what are the relative percentages of the isotopes?

2 answers

There is little point in posting the same question twice within a couple of minutes.

Let the fraction of 60Q be x and therefore the fraction of 63Q is 1-x.

60x +(1-x)63=60.5

can you take it from here?
14