6)
Metoda 1
a/b=7/5 = k
a=7k si b=5k
a*b=1260
7k*5k=1260
35k²=1260
k²=1260:35
k²=36⇒ k=6
a=7*6=42 si b=5*6=30
Metoda 2
a=7b/5
7b/5*b=1260
7b²=1260*5
7b²=6300
b²=6300:7
b²=900
b=30
a=7*30:5=42
8)
D66={1,2,3,6,11,22,33,66}
1/2 = 3/6 = 11/2 2= 33/66
