Final answer:
Dillon sold 11 boxes of candy in total.
Step-by-step explanation:
To find out how many boxes of candy Dillon sold, we need to calculate how much candy he sold compared to Regan. Since Dillon sold 2 5/8 times as much as Regan, we can multiply Regan's sales by this factor. Regan sold 4 boxes of candy, so we multiply that by 2 5/8:
4 x 2 5/8 = 10 1/2 boxes
Therefore, Dillon sold 10 1/2 boxes of candy. However, since we can't have half a box of candy, we round up to the nearest whole number. So Dillon sold 11 boxes of candy.