Multiple references with a single footnote

Question

I am having some problems with referencing multiple parts of my text in a single footnote. I already have tried it all. The image is shos the part that I can´t do a reference. The original footnote is a little above

\documentclass{article}
\usepackage{cleveref}
\begin{document}
\begin{align*}
&\begin{alignedat}{1}
P\biggl[Z_{1-\alpha} > \frac{18 + \frac{10}{7} - \bar{x}}{\sigma}\biggl]
\end{alignedat}
=
\begin{alignedat}{1}
P\biggl[Z_{1-\alpha} > \frac{\cancel{18}+ \frac{10}{7} - \cancel{18}}{1.14455}\biggl]
\end{alignedat}
=
\\[1ex]
= \hspace{0.1cm}
&\begin{alignedat}{1}
P\biggl[Z_{1-\alpha} > \frac{\frac{10}{7}}{1.14455}\biggl]  =P\biggl[Z_{1-\alpha} > 1.248151\biggl]
\end{alignedat}
=
\\
\stackrel{\footnotemark}{\approx}\hspace{0.1cm}
&\begin{alignedat}{1}
 0.106 = 10.6  \%
\end{alignedat}
\end{align*}
\footnotetext{\textbf{1 - }Valores determinados com base em aproximações a valores mais próximos na tabela de quantis da função de distribuição normal padrão.\label{note1}}
\begin{align*}
    &\begin{alignedat}{1}
    P\biggl[17< Dur < 20\biggl]
    \end{alignedat}
    =
    \begin{alignedat}{1}
    P\biggl[\frac{17 - \bar{x}}{\sigma}<\frac{Dur - \bar{x}}{\sigma} < \frac{20 - \bar{x}}{\sigma}\biggl]
    \end{alignedat}
    = \\[1ex]
    =\hspace{0.1cm}
    &\begin{alignedat}{1}
    P\biggl[\frac{17 - \bar{x}}{\sigma}< Z_{1-\alpha}< \frac{20 - \bar{x}}{\sigma}\biggl]
    \end{alignedat}
    = 
    \begin{alignedat}{1}
    P\biggl[\frac{17 - 18}{1.14455}< Z_{1-\alpha} < \frac{20 - 18}{1.14455}\biggl]
    \end{alignedat}
    =\\[1ex]
    = \hspace{0.1cm}
    &\begin{alignedat}{1}
    P\biggl[-0.873706< Z_{1-\alpha} < 1.747412\biggl]
    \end{alignedat}
    = \\[1ex]
    = \hspace{0.1cm}
    &\begin{alignedat}{1}
    1-\biggl(P\biggl[-0.873706< Z_{1-\alpha}\biggl] + P\biggl[1.747412>Z_{1-\alpha}\biggl]\biggl)
    \end{alignedat} 
    =\\
    =\hspace{0.1cm}
    &\begin{alignedat}{1}
    1- Z_{1-\alpha}(0.873706) - Z_{1-\alpha}(1.747412) \stackrel{{1}}{\approx} 1 - 0.192 - 0.0401 
    \end{alignedat} 
    =\\[1ex]
    =\hspace{0.1cm}
    &\begin{alignedat}{1}
    0.7679 = 76.79\%
    \end{alignedat} 
    \end{align*}
\end{document}

Answer 1

This uses \footnotemark[\getrefnumber{note1}] (refcount package) to reproduce the formatting precisely. \text{\textsuperscript{\ref{note1}}} also works.

I also cleaned up the code a bit.

\documentclass{article}
\usepackage{refcount}
\usepackage{amsmath}
\usepackage{cleveref}

\def\cancel{}% could not find in any package

\begin{document}
\begin{align*}
&
P\biggl[Z_{1-\alpha} > \frac{18 + \frac{10}{7} - \bar{x}}{\sigma}\biggl]
=
P\biggl[Z_{1-\alpha} > \frac{\cancel{18}+ \frac{10}{7} - \cancel{18}}{1.14455}\biggl]
=
\\[1ex]
= \null
&
P\biggl[Z_{1-\alpha} > \frac{\frac{10}{7}}{1.14455}\biggl]  =P\biggl[Z_{1-\alpha} > 1.248151\biggl]
\\
\stackrel{\footnotemark}{\approx} \null&
 0.106 = 10.6  \%
\end{align*}
\footnotetext{Valores determinados com base em aproximações a valores mais próximos na tabela de quantis da função de distribuição normal padrão.\label{note1}}
  \begin{align*}
    &
    P\biggl[17< Dur < 20\biggl]
    =
    P\biggl[\frac{17 - \bar{x}}{\sigma}<\frac{Dur - \bar{x}}{\sigma} < \frac{20 - \bar{x}}{\sigma}\biggl]
    = \\[1ex]
    =\null
    &
    P\biggl[\frac{17 - \bar{x}}{\sigma}< Z_{1-\alpha}< \frac{20 - \bar{x}}{\sigma}\biggl]
    = 
    P\biggl[\frac{17 - 18}{1.14455}< Z_{1-\alpha} < \frac{20 - 18}{1.14455}\biggl]
    =\\[1ex]
    = \null
    &
    P\biggl[-0.873706< Z_{1-\alpha} < 1.747412\biggl]
    = \\[1ex]
    =\null
    &
    1-\biggl(P\biggl[-0.873706< Z_{1-\alpha}\biggl] + P\biggl[1.747412>Z_{1-\alpha}\biggl]\biggl)
    =\\
    =\null
    &
    1- Z_{1-\alpha}(0.873706) - Z_{1-\alpha}(1.747412) \stackrel{\footnotemark[\getrefnumber{note1}]}{\approx} 1 - 0.192 - 0.0401 
    =\\[1ex]
    =\null
    &
    0.7679 = 76.79\%
    \end{align*}
\end{document}