Răspuns:
[tex]7\frac{1}{2} =\frac{7*2+1}{2} =\frac{15}{2} =7,5km[/tex]
[tex]\frac{3}{4} =0,75km[/tex]
100%...........7,5km
x..................0,75km
--------------------------
x=0,75*100:7,5=10 zile
[tex]10\frac{1}{2} =\frac{21}{2} =10,5km[/tex]
12zile....10,5km
1 zi.............x
-------------------------
x=10,5:12=0,875 km a alergat pe zi