Find the cost of installing a fence around all sides of a rectangular yard that is 50 feet by 90 feet. The fence that is being used costs $8.50 per foot.

Answer 1

The perimeter of the rectangular yard is $50+50+90+90=<<50+50+90+90=280>>280$ feet.
The cost of installing a fence around all sides of the yard is $280*8.50=$<<280*8.5=2380>>2380. Answer: \boxed{2380}.