To find the number of cheese slices sold, we must first find the total number of patrons surveyed. Adding up the number of patrons for each type of pizza:
9 (cheese) + 5 (pepperoni) + 6 (sausage) + 7 (veggie) = 27
Next, we need to find the proportion of cheese patrons out of the total patrons surveyed:
9 cheese patrons / 27 total patrons = 0.3333 (rounded to 4 decimal places)
Finally, we multiply this proportion by the total number of slices of pizza sold:
0.3333 * 1299 slices = 433 patrons
Therefore, the number of cheese slices sold would be 433 slices.