You can put this solution on YOUR website! .
For every 6 boys there are 9 girls there is 600 people there what is the ratio between boys and girls
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1. If all 600 people are boys and girls (and not men and women)
and
2. if your question does relate to these 600 girls and boys (and not to some other 600 people)
then the ratio is = .
To be honest, it is still unclear to me: to what population relates your question?