To do Alt + H L T B on Mac in Excel, download and install Accelerator Keys, then press Option, followed by H, L, T, b.
Command: Format Bottom 10 Items
This is how to do Alt + H L T B on Mac in Excel with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with Excel.
Alt + H L T B highlights the bottom 10 items (by value) in your selection. You can change the number of items to highlight.