1
fiul=a tata=a+25 bunicul = 3x(a+25) a+a+25+3(a+25)=125 2a+25+3a+75=125 5a+25+75=125 5a+25=125-75 5a+25=50 5a=50-25 5a=25 a=5 fiul = 5 tata=25+5=30 bunicul=3x30=90 verific 90+30+5=125
2
x+x+1+x+2+x+3+x+4=2510 5x+1+2+3+4=2510 5x+10=2510 5x=2510-10 5x=2500 x=2500:5 x=500 x+1=501 x+2=502 x+3=503 x+4=504