Răspuns:
[tex] \frac{13}{10} \times \frac{1}{13x} = \frac{23}{9} \times \frac{15}{90} = [/tex]
[tex] \frac{1}{10x} = \frac{23}{9 \times 6} = > x = \frac{54}{230} = \frac{27}{115} [/tex]
