Răspuns :

[tex]1.3(x) = \frac{25}{18} \\ \\ 1\frac{x3 - 3}{90} = \frac{25}{18} \\ \\ \frac{1 \times 90 + (x3 - 3}{90} = \frac{25}{18} \\ \\ \frac{90 + (3x - 3)}{ 90} = \frac{25}{18} \\ \\ \frac{90 + 3x - 3}{90} = \frac{25}{18} \\ \\ \frac{87 + 3x}{ 90} = \frac{25}{18} \\ \\ \frac{3(29 + x)}{90} = \frac{25}{18} \\ \\ \frac{29 + x}{30} = \frac{25}{18} \\ \\ 18 \times (29 + x) = 30 \times 25 \\ \\ 522 + 18x = 750 \\ \\ 18x = 228 \\ \\ x = 228 \div 18 \\ \\ x = \frac{228}{18} \\ \\ x = \frac{38}{3} [/tex]