Răspuns :
a+(a+1)+(a+1+1)=48
3a+3=48
3a=48-3
3a=45
a=45:3
a=15=>a+1=16
=>a+1+1=17
VERIFICARE:15+16+17=31+17=48
3a+3=48
3a=48-3
3a=45
a=45:3
a=15=>a+1=16
=>a+1+1=17
VERIFICARE:15+16+17=31+17=48