SOLUTION: Each student at Sussex Elementary School takes one foreign language. Two thirds of the students take Spanish, 1/9 take French, 1/18 take German, and the rest take some other foreig

Algebra ->  Proofs -> SOLUTION: Each student at Sussex Elementary School takes one foreign language. Two thirds of the students take Spanish, 1/9 take French, 1/18 take German, and the rest take some other foreig      Log On


   

Question 571456: Each student at Sussex Elementary School takes one foreign language. Two thirds of the students take Spanish, 1/9 take French, 1/18 take German, and the rest take some other foreign language. if there are 720 students in the school, how many do not take Spanish, French, and German?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Each student takes 1 language, so this
problem is like a pie chart. All the slices add
up to 1.
Let the fraction of students who do not take
Spanish, French, and German = x
+2%2F3+%2B+1%2F9+%2B+1%2F18+%2B+x+=+1+
Multiply both sides by 18
+12+%2B+2+%2B+1+%2B+18x+=+18+
+18x+=+18+-+15+
+18x+=+3+
+x+=+1%2F6+
+%281%2F6%29%2A720+=+120+
120 students do not take Spanish, French, and German