Question

Tatal si fiul au impreuna 37 de ani. Peste 16 ani tatal va fi de doua ori mai in varsta decat fiul. Determinati varsta fiului.

Answer 1

a+b=37
a=2b+16
2b+16+b=37
3b+16=37
3b=21
b=21:3
b=7 ani are fiul
a+7=37
a=37-7
a=30 ani are tatal

Answer 2

$t+f=37 \\\\ t+16=2(f+16) \\\\ t+16=2f+32 \\\\ t=2f+32-16 \\\\ \underline{t=2f+16} \\\\\\ 2f+16+f=37 \\\\ 3f=37-16 \\\\ 3f=21 \\\\ \boxed{f=7 \ ani \ are \ fiul} \\\\ t=37-7 \\\\ \boxed{t=30 \ ani \ are \ tatal}$