To find out how many whole friendship bracelets Bryan can make with 523 feet of leather cord, we need to divide the total length of the cord by the length needed for each bracelet.
The calculation is:
\[ \text{Number of bracelets} = \frac{523 \text{ feet}}{12 \text{ feet/bracelet}} = 43.5833 \]
Since Bryan can only make whole bracelets, we round down to the nearest whole number.
Thus, Bryan can make 43 whole bracelets.