We have to find how many bracelets she starts with.
We can call it x by now.
If she sold half, she keeps x/2.
Then, she bought 20 more, so the final number is x/2 + 20.
We also know that this final number is 45, so we can write and solve for x:
[tex]\begin{gathered} \frac{x}{2}+20=45 \\ \frac{x}{2}=45-20 \\ \frac{x}{2}=25 \\ x=25\cdot2 \\ x=50 \end{gathered}[/tex]Answer: she starts with 50 bracelets.
