Final answer:
After Luis and Joey eat portions of a 16-ounce box of cereal, there are 2 ounces left.
Step-by-step explanation:
To find the number of ounces left in the box of cereal, we need to subtract the amount eaten by Luis and Joey from the original 16 ounces. Luis has eaten (5/8) of the box, which is equal to (5/8) * 16 = 10 ounces. Joey has eaten (1/4) of the box, which is equal to (1/4) * 16 = 4 ounces. Therefore, the number of ounces left in the box is 16 - 10 - 4 = 2 ounces.