In 2010 Elmbrook Middle School had 100 students in the eighth grade. In 2011 the number of eighth
graders decreased by 10%. The 2012 eighth grade Class increased in size by 10% from 2011. How many
eighth grade students were enrolled at Elmbrook Middle School in 2011
So, if you have 100 students to start and it decreases by 10% then take the 100 and multiply it by .10. You should get 10. Then, subtract 10 from 100 and you end up with 90.
