Răspuns:
125, 250, 375
Explicație pas cu pas:
(bc) = 20% • (abc)
5(bc) = (abc)
5(bc) = 100a + (bc)
4(bc) = 100a
a=1 => 100÷4 = 25 => (bc) = 25 => (abc) = 125
a=2 => 200÷4 = 50 => (bc) = 50 => (abc) = 250
a=3 => 300÷4 = 75 => (bc) = 75 => (abc) = 375
a=4 => 400÷4 = 100, dar 0<(bc)<100