How is the percentage rate calculate to get the answer?

$\backslash$table$[[$Weekly Tracking,Customers,Containers,Percentage Rate$],[],[$Monday$,$Fruits,$90,30,,],[$Meats$,110,90,78\mathrm{.}00\%,],[$Snacks$,200,10,,],[$Tuesday$,$Fruits,$95,50,,],[$Meats$,110,75,67\%,],[$Snacks$,205,110,,],[$Wednesday$,$Fruits,$100,60,,],[$Meats$,120,60,85\%,],[$Snacks$,220,162,,],[$Thursday$,$Fruits,$110,31,,],[$Meats$,125,43,63\%,],[$Snacks$,235,211,,],[$Friday$,$Fruits,$130,95,,],[$Meats$,180,90,76\%,],[$Snacks$,310,176,,],[$Saturday$,$Fruits,$100,67,,],[$Meats$,180,15,85\%,],[$Snacks$,310,110,,],[$Sunday$,$Fruits,$110,45,7,],[$Meats$,125,94,85\%,],[$Snacks$,235,117,4,],[$Weekly Totals,,Total Sales: $3400,,$Average Sale Rate,$77\%$