What's so special about the relationship between
parallel and perpendicular

the given 6 = w/p is equivalent to 6p = w, where w is the total area of the walls and p is the area covered by a single can of paint.

knowing that 6 cans of paint will be needed, 6p = w becomes 6(6) = w = 36.   this tells us that the total area to be painted is 36 square units.

-1/4 > -1 2/3. -1/4 is greater than -1 2/3 because it is closer to 0 on the number line.