Let the original cost of the jacket be x.
Now, saying that one-third of the original cost of the jacket is $34, is mathematically equivalent to:
[tex]\frac{1}{3}\times x=34[/tex]Now we have to solve the resulting equation in order to obtain the value of x
This is done as follows:
[tex]\frac{1}{3}\times x=34[/tex][tex]\Rightarrow\frac{x}{3}=34[/tex][tex]\Rightarrow x=3\times34[/tex][tex]x=102[/tex]Therefore, the original cost of the jacket is $102