Answer:
[tex]160[/tex] dollars
Step-by-step explanation:
Let [tex]a[/tex] be the number of money that Shane had at the beginning of the trip. It says that [tex]200[/tex] dollars is [tex]25 \%[/tex] more than [tex]a[/tex]. So, [tex]125 \%[/tex] of [tex]a[/tex] should be the same number as [tex]200[/tex] dollars.
Writing [tex]125 \%[/tex] in its decimal form:
[tex]125(\%) \\ 125(\frac{1}{100}) \\ \frac{125}{100} \\ 1.25[/tex]
Solving for [tex]a[/tex]:
[tex]1.25a = 200 \\ \frac{1.25a}{1.25} = \frac{200}{1.25} \\ a = 160[/tex]