711 is 1450% of b+c and b is 58% of c what is the value of c

hi.... soooo i am writing the nov sat and where do i write the practices tests which are hard and are official sat level cause i wrote all the tests in bluebook and i have no money for aniko i wanna something which is free of cost and its difiiculty is sat official level pls suggest i only have 12 days for sat

pls telll

pls

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