Datele problemei
a, b → cele doua numere
a : b = 9 rest 1 ⇒ a = 9 × b + 1
( a + b ) : ( a -b) + 1 rest 4
a + b = a - b + 4
a - a + b + b = 4
2 × b = 4
b = 4 : 2
b = 2 → al doilea numar
a = 9 × 2 + 1
a = 19 → primul numar
Verific:
19 : 2 = 9 rest 1
19 + 2 = 19 - 2 + 4 = 21