Notam numerele cu a, b si c.
a = b × 3/5
b = c × 4/5
Atunci a = (c × 4/5) × 3/5 = c × 12/25
Dar a × c = 4800, adica:
c × 12/25 × c = 4800
c^2 × 12/25 = 4800
c^2 = 4800 : (12/25) = 4800 × 25/12 = 400 × 25 =2^4 × 5^2 × 5^2 =2^4 × 5^4
Atunci c = radical (2^4 × 5^4) = 2^2 × 5^2 = 4 × 25
c = 100
b = c × 4/5 = 100 × 4/5 = 20 × 4/1 = 80
a = B × 3/5 = 80 × 3/5 = 16 × 3/1 = 48
R: Numerele sunt 48, 80 si 100