3 cans of paint (with a fair amount left over in the 3rd can)
The perimeter length of the room is the sum of the lengths of the walls. Since opposite walls are the same length, we can add adjacent wall lengths and multiply by 2.
... perimeter = 2(10' + 8') = 36'
The wall area is that length times the height, so is ...
... wall area = 6' × 36' = 216 ft²
Two cans of paint will cover the first 200 ft², and it wil take part of a 3rd can to cover the remaining 16 ft².
... 3 cans of paint are required
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If your window and door area totals more than 16 ft², then you will only need 2 cans of interior paint.
