First you need to find the surface area of the wall that was painted, and then add the additional area in the hallway that was painted.
The wall that was painted was 9 feet by 10 feet, or 90 square feet. 90 square feet plus the additional 46 square feet in the hallway is 136 square feet, which is the total area that the paint covered.
Stretch Your Thinking I am a multiple of 10. My factors include an even number and an odd number. I am greater than 3 x 5 and less than 4 x 7. What number am I?
