The following worksheet shows a diagram of a grass yard that needs to be watered. There are two types of in-ground sprinkler heads available to water the yard: a full circle sprinkler head and a 125 degree sprinkler head.
Can you find the number of sprinklers of each type and position each sprinkler to minimize water cost?
(adapted from the following blog post: http://musingmathematically.blogspot.com/2012/07/sprinkler-task.html)