Calculate rom sixes and House size

calc.rb

def sqm_to_sqft(num)
   num*10.763910
end

# http://www.espc.com/properties/details.aspx?pid=315620&sid=25446441807
data = [ 
  [3.75, 3.32],
  [2.95, 2.87],
  [3.78, 2.47],
  [1.88, 1.45],
  [2.13, 1.88],
  [3.68, 3.14],
  [1.55, 1.46],
  [3.27, 2.59],
  [2.66, 2.59],
  [2.87, 2.03],
  [2.16, 1.98],
  [1.88, 0.93]]

room_sizes = data.collect{ |room| room.reduce(:*) }
house_size = room_sizes.reduce(:+)

puts house_size.to_s + " m^2"
puts sqm_to_sqft( house_size ).to_s + " \"^2"

the_grahame = [
[3.11, 2.8],
[1.8,2.8],
[3.16, 5.3],
[3.16,2.81],
[2.50,1.14],
[2.5,1.8],
[2.5,2.19],
[3.74,3.34],
[4.32,2.84],
[2.6,3.48],
[3.18,2.89],
[2.25,2.34],
[2.09,1.81],
[2.60,1.73]]