Hi @Heena1
You can use the count-selected() function to count the number of choices selected by the user. For example, count-selected(${business}). For more info, see the Formulas documentation.
There isn't a function for counting the total number of choices in a choice list. If the total number of choices is unlikely to change frequently, you could just hard-code this number into the summary report template.
Hope this helps! Best, Jim