Question

Nelu si Tudor au impreuna 1716 bile.Cat are fiecare ,daca Tudor are cu 90 mai putine decat Nelu?

Answer 1

n-Nelu
t-Tudor

n+t=1716 bile
n=t+90

2t+90=1716
2t= 1716-90
2t=1626
Tudor are 1626/2=813
Nelu are 813+90=903 bile

Answer 2

n  |----------------t------------|...90..|
t   |----------------t------------|            }1716

t+90+t=1716
2t=1626
t=813  tudor

deci 
813+90=903  are nelu