There is a 5,200 sq. ft. house and a 7,300 sq. ft. house next to each other. The smaller house is being expanded. If the new total square footage of both houses is 16,000 sq. ft., how much is the smaller house being expanded by, in sq. ft.?
Originally, the houses are 7300+5200=<<7300+5200=12500>>12500 sq. ft. in total.
The smaller house will be expanded by 16000-12500=<<16000-12500=3500>>3500 sq. ft.
#### 3500