Find the total spent on the food:
10.49 x 6 = 62.94
10.50 x 6 = 63.00
6.75 x 6 = 40.50
Total = 62.94 + 63.00 + 40.50 = $166.44
Next find the total in sales:
47.70 x 21 = $1001.70
Profit = total sales - cost of food:
Profit = 1001.70 - 166.44 = $835.26