What you want is half of 7⅓. The easiest way is to convert the number to an improper fraction. 7 wholes is 21 thirds, written 21/3, and we add another third: 22/3. Now it’s easy to halve this, because we divide 22 by 2 to get 11, so we end up with 11/3. Now we convert this to a mixed number: 3 goes into 11 3 times with a remainder of 2. So we have whole number 3 plus remainder 2, which means we have ⅔ to add to the whole, making 3⅔ brownies each.