77. Person A and Person B start from locations $\mathrm{A}$ and $\mathrm{B}$ respectively at the same time, heading towards each other. At the start, their speed ratio is $3: 2$. After their first meeting, Person A's speed increases by $20\%$, and Person B's speed increases by $30\%$. When Person A reaches location B, Person B is still 14 kilometers away from location $\mathrm{A}$. Therefore, the distance between $\mathrm{A}$ and $\mathrm{B}$ is $\qquad$ kilometers.
Reference answer: 45