Răspuns :
notam x numarul de pagini a cartii
[tex] \frac{4}{7}x=120=>x= \frac{7*120}{4}=>x=7*30=210 [/tex]
[tex] \frac{4}{7}x=120=>x= \frac{7*120}{4}=>x=7*30=210 [/tex]