Question by Summer Clouds - Discuss with MathYouLike

Summer Clouds moderators

19/09/2017 at 08:59

What is the value of 122 × 71 modulo 11?

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Phan Thanh Tinh Coordinator 19/09/2017 at 09:59

122 x 71 = (11² + 1)(11 x 6 + 5)

= 11³ x 6 + 11² x 5 + 11 x 6 + 5 \(\equiv5\left(mod11\right)\)

So, the answer is 5
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Vũ Trung Dũng 24/09/2017 at 14:16

122 x 71 = (112 + 1)(11 x 6 + 5)

= 113 x 6 + 112 x 5 + 11 x 6 + 5 $\equiv 5 (m o d 11)$

So, the answer is 5

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