document.write( "Question 923820: A certain school has 720 pupils. The ratio of the number of senior pupils to the number of junior pupils is 4 : 5. How many junior pupils are there in the school? \n" ); document.write( "

Algebra.Com's Answer #560337 by ewatrrr(24785) $\"\"$ $\"About$

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document.write( "Hi
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document.write( "The ratio of the number of senior pupils to junior pupils is 4 : 5
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document.write( "Let x represent the constant of proportionality
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document.write( "4x + 5x = 720
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document.write( "9x = 720
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document.write( "x = 80
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document.write( "5x = 400, the number of junior pupils  in the school. \n" );
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