SOLUTION: 70 percent of the 100 students in a middle school class cafeteria bought their lunch. Some of the students that bought their lunch leave the cafeteria to attend an assembly. Now

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: 70 percent of the 100 students in a middle school class cafeteria bought their lunch. Some of the students that bought their lunch leave the cafeteria to attend an assembly. Now       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 774509: 70 percent of the 100 students in a middle school class cafeteria bought their lunch. Some of the students that bought their lunch leave the cafeteria to attend an assembly. Now only 60 percent of the remaining students bought their lunch. How many students are remaining?
Thanks in advance for your help from a father trying to help his daughter.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
70 percent of the 100 students in a middle school class cafeteria bought their lunch.
Some of the students that bought their lunch leave the cafeteria to attend an assembly. Now only 60 percent of the remaining students bought their lunch.
How many students are remaining?
:
Let x = number of student that left
:
%2870-x%29%2F%28100-x%29 = .6
multiply by (100-x)
70 - x = .6(100 - x)
70 - x = 60 - .6x
70 - 60 = x - .6x
10 = .4x
x = 10/.4
x = 25 students left
therefore
100-25 = 75 students remain