Question

aflati toate nr de forma abc care verifica egalitatea abc-cba=396

Answer 1

abc - cba = 396

100a + 10b + c - 100c - 10b - a = 396

99a - 99c = 396

99 × (a - c) = 396

a - c = 396 : 99

a - c = 4 ; a si c diferite de 0

9 - 5 = 4

8 - 4 = 4

7 - 3 = 4

6 - 2 = 4

5 - 1 = 4

(a; c) = (9; 5), (8; 4), (7; 3), (6; 2), (5; 1)

b = 0; 1; 2; 3; 4; 5; 6; 7; 8 ; 9 .

asadar,

abc poate avea 5 × 10 = 50 de valori
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