Answers

2014-04-18T20:35:47+05:30
Let the number of students be x
no. of girls=5x/8
no.of boys=3x/8
5x/8=120+3x/8
2x/8=120
therefore x=480
no of boys is 3(480)/8=180
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2014-04-18T22:58:01+05:30
When such type of questions are asked let the quantity be variableand then solve it 
solution:
      
             no.of students = x =>girls=5/8x and boys=1-(5/8x)=3/8x
             but 5/8x=120+3/8x
             =>x=480  =>boys=180 and girls=300
 
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