Answer:
 Carpet needed = 320 square feet.
Explanation:
Given: Andre’s apartment is 800 square feet. If he wants to carpet 40% of it.
To find: How much carpet will he need .
Solution: We have given that 
 Andre’s apartment = 800 square feet .
 Andre wants to carpet 40% of 800 square feet .
According to question 
carpet needed = 40% of 800.
Carpet needed = 
 .
 .
Carpet needed = 320 square feet.
Therefore , Carpet needed = 320 square feet.