1
fie x suma de bani
in prima zi cheltuie 2x/3 si lasa un rest de x/3
in adopua zi cheltuie (5/7)*x/3= 5x/21
raman
deci 2x/3+5x/21+60=x
14x/21+5x/21+60=x
19x/21+60=x
60=x-19x/21
60=21x/21-19x/21
60=2x/21
2x=60*21
x=60*21:2
x=30*21
x=630 lei
2
fie d , drumul
in prima zi, d/4
a doua zi, 2d/5
a treia zi d/6
apatra ,77 km
d/4+2d/5+d/6+77=d
15d/60+24d/60+10d/60+77=d
49d/60+77=d
77=d-49d/60
77=11d/60
7=d/60
7*60=d
d=420km
