Respuesta :
let the score on her seventh test be "x".
SO,
[tex] \frac{83+92+79+88+89+95+x}{7} =90\\\\ \frac{526+x}{7}=90\\\\ 526+x=630\\\\x=630-526\\\\ \boxed{x=104} [/tex]
∴ He must get 104% on his seventh test to get an average score of 90%
SO,
[tex] \frac{83+92+79+88+89+95+x}{7} =90\\\\ \frac{526+x}{7}=90\\\\ 526+x=630\\\\x=630-526\\\\ \boxed{x=104} [/tex]
∴ He must get 104% on his seventh test to get an average score of 90%