x= lungimea totala a drumului
[tex] \frac{20}{100}x [/tex]=[tex] \frac{x}{5} [/tex]= cat a parcurs in prima zi
[tex] \frac{50}{100}x= \frac{x}{2} [/tex]= cat a parcurs a doua zi.
60= cat a parcurs a treia zi.
[tex] \frac{x}{5}+ \frac{x}{2}+ \frac{60}{1}= \frac{x}{1} \\ 2x+5x+600=10x \\ 2x+5x-10x=-600 \\ -3x=-600 \\ x=(-600):(-3) \\ x=+200 \\ x=200 lei initial [/tex]