Question

Tatal are 50 de ani iar fiul 20 de ani de ani. Cu cati in urma tatal era de 4 ori mai in varsta decat fiul

Answer 1

50-x=4(20-x)
50-x=80-4x
4x-x=80-50
3x=30
x=10 ani 

Answer 2

50..........................20
49..........................19
48..........................18
47..........................17
46..........................16
45..........................15
44..........................14
43..........................13
42..........................12
41.......................... 11
40...........................10
tata 40......fiul 10

40:10=4
40 mai mare decat 10 de 4 ori