If QT = 74 and RS = 91, what is PU?

The trapezoids in the picture follow the next proportion:
[tex]\frac{PU}{QT}=\frac{QT}{RS}[/tex]Replacing with data and solving for PU,
[tex]\begin{gathered} \frac{PU}{74}=\frac{74}{91} \\ PU=\frac{74\cdot74}{91} \\ PU=60.18 \end{gathered}[/tex]