Each room has 2 walls that are 4x10 = 40 square feet and 2 walls that are 8x10 = 80 square feet. So 80+80+40+40 = 240 square feet of wall will be painted per room.
We use 2 coats of paint so in effect, we double the area. Imagine laying one thin wall on top of the other. The amount of paint area used per room doubles from 240 to 480
There are 4 of these rooms so 4*480 = 1920
The total area we need to paint is 1920 square feet
Divide this over 32 to get 1920/32 = 60
Final Answer: 60