Question

cate nr de forma abc care verifica relatia abc+a=cba+c exista?

Answer 1

abc + a = cba + c

100a + 10b + c + a = 100c + 10b + a + c

101a + 10b + c = 101c + 10b + a

101a - a = 101c - c

100×a = 100×c | : 100

a = c ; a si c diferite de 0

asadar,

a = c = 1; 2; 3; 4; 5; 6; 7; 8; 9 --> ( 9 valori )

b = 0; 1; 2; 3; 4; 5; 6; 7; 8; 9 --->( 10 valori )


9 × 10 = 90 de numere de forma abc
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