Question

Hallar la suma de cifras de S.

S=(666...67)²

Answer 1

7×7 = 49. =>4(1) + 8(0) + 9

67×67 = 4489. =>4(2) + 8(1) + 9

667×667 =444889=>4(3) + 8(2) + 9

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66...67×66...67

$\frac{66...67}{n \: cifras} \times \frac{66...67}{n \: cifras} = 4(n) \: + \: 8(n - 1) \: + 9$

Answer 2

7×7 = 49. =>4(1) + 8(0) + 9

67×67 = 4489. =>4(2) + 8(1) + 9

667×667 =444889=>4(3) + 8(2) + 9

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66...67×66...67

\frac{66...67}{n \: cifras}   \times  \frac{66...67}{n \: cifras}  = 4(n) \:  +  \: 8(n - 1) \:  + 9