Percent decrease : (original number - new number) / original number..*100
= (225,000 - 191,250) / 225,000.....* 100
= 33,750 / 225,000....* 100
= 0.15 * 100
= 15% decrease <==
You should expect about 2400 successes because as a percent .4=40%
20
There are 10 feet of posts on each side. That means there are 40 feet of fencing in total. If you divide that by two (to represent posts being 2 feet apart) then you get 20. There are 20 posts needed.