Răspuns:
a)
amplificam 4/5 cu 4 => 16/20
amplificam 7/10 cu 2 => 14/20
amplificam 3/4 cu 5 => 15/20
14/20; 15/20 ; 16/20
=> 7/10 ;3/4 ; 4/5
b)
amplificam 2/3 cu 24 => 48/72
amplificam 4/9 cu 8 => 32/72
amplificam 20/24 cu 3 => 60/72
32/72 ; 48/72 ; 60/72
=> 4/9 ; 2/3 ; 20/24
c)
amplificam 11/12 cu 20 => 220/240
amplificam 6/16 cu 15 => 90/240
amplificam 25/30 cu 8 => 200/240
90/240 ; 200/240 ; 220/240
=> 6/16 ; 25/30 ; 11/12
coroana?
