Note: the juice is 20% of the original amount, not of the remainder.
\\(\begin{aligned}
\text{Sandwich} &= 30\% \text{ of original}
\\
\text{Juice} &= 20\% \text{ of original}
\\
\text{Total after sandwich + juice} &= 50\% \text{ remaining}
\\
\text{Cookie: 25\% of remainder} &= 0.25 \times 50\% = 12.5\% \text{ of original}
\\
\text{Left} &= 50\% - 12.5\% = 37.5\% = \$42
\\
\text{Original} &= \$42 \div 0.375 = \$112
\end{aligned}\\)
Final Answer: \$112