# How do you align equations parts vertically?

I have read many other solutions but this situation seems unique.

\documentclass{exam}
\usepackage{multicol}
\usepackage{amsmath}
\begin{document}
\begin{questions}
\question Simplify the following:
\begin{multicols}{4}
\begin{parts}
\part $8^\frac{2}{3}$
\part $\dfrac{16^{\frac{2}{3}}}{16^{\frac{1}{6}}}$
\part $9^\frac{1}{3}\cdot 9^{-\frac{5}{6}}$
\part $\left(25^{\frac{1}{3}}\right)^{\frac{3}{2}}$
\end{parts}
\end{multicols}
\end{questions}
\end{document}

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Welcome to TeX.SE! –  Christian Hupfer Apr 24 at 5:29

The heights of the four part letters is different, because the different heights of the formulas. The following example defines \vphantomB with an invisible box of the greatest height of part (b):

\documentclass{exam}
\usepackage{multicol}
\usepackage{amsmath}
\begin{document}
\begin{questions}
\question Simplify the following:
\begin{multicols}{4}
\def\vphantomB{\leavevmode\vphantom{$\dfrac{16^{\frac{2}{3}}}{}$}}
\begin{parts}
\part \vphantomB $8^\frac{2}{3}$
\part $\dfrac{16^{\frac{2}{3}}}{16^{\frac{1}{6}}}$
\part \vphantomB $9^\frac{1}{3}\cdot 9^{-\frac{5}{6}}$
\part \vphantomB $\left(25^{\frac{1}{3}}\right)^{\frac{3}{2}}$
\end{parts}
\end{multicols}
\end{questions}
\end{document}


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Thank you very much....this issue has haunted me for a while. –  Garth Apr 24 at 14:45

you can use the package enumitem instead:

documentclass{exam}
\usepackage{amsmath}
\usepackage[inline]{enumitem}
\begin{document}
\begin{questions}
\question Simplify the following:

\begin{enumerate*}[label*=(\alph*),itemjoin={\hfill}]
\item $8^\frac{2}{3}$
\item $\dfrac{16^{\frac{2}{3}}}{16^{\frac{1}{6}}}$
\item $9^\frac{1}{3}\cdot 9^{-\frac{5}{6}}$
\item $\left(25^{\frac{1}{3}}\right)^{\frac{3}{2}}$
\end{enumerate*}
\end{questions}

\end{document}


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In this solution, if you have too many items, there is no vertical alignment betwen the items in different lines. –  Bernard Apr 24 at 12:01
Thank you very much....this issue has haunted me for a while. –  Garth Apr 24 at 14:45