A homeowner is laying sod in her lawn. The lawn is a rectangle with dimensions of 28'*18'. If one piece of sod is a rectangle with dimensions of 60cm*40cm, approximately how many pieces of sod should the homeowner order?

Answer 1

28' = 853.44 cm
18' = 548.64 cm

Easy way, assuming partial pieces are tucked in as needed:

(853*548)/(60*40) = 195

Now, you can do several kinds of approximation, requiring whole pieces, etc. One easy way is to round up the lawn area to multiples of 40 and 60:

853/60 = 14.2, round up to 15
548/40 = 13.7, round up to 14

So, the lawn is about 15 by 14 sods in size, requiring 210 pieces.

The actual optimal value is somewhere in between those two values.