A 25 story building has 4 apartments on each floor. If each apartment houses two people, how many people does the building house?
If each building floor has 4 apartments, we have 25 floors * 4 apartments/floor = <<25*4=100>>100 apartments.
If each apartment has 2 people, 100 apartments * 2 people/apartment = <<100*2=200>>200 people.
#### 200