Of the girls who attend primary school are 30% blondes and 70% brunette. 81% blondes and 19% brunette has blue eyes.

How many girls attending school altogether if 470 girls has blue eyes?


x =  1250


470 = (81/100)*(30/100)*x + (19/100)*(70/100)*x

37.6x = 47000

x = 1250

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