Răspuns :
[tex]\text {Metoda~grafica~:}[/tex]
D |-----| } 12 bilete
S |-----|-----|-----|
12:4=3 bilete (un segment)
D=3 bilete
S=3×3=9 bilete
D |-----| } 12 bilete
S |-----|-----|-----|
12:4=3 bilete (un segment)
D=3 bilete
S=3×3=9 bilete