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The expression 79 + 97 is divisible by 64.

Answers (1)

The given statement is True.

Given: 79 + 97 is divisible by 64.

Now,

79 + 97 = (1+8)7 – (1-8)9

             = [7C0 + 7C1.8  + 7C2.(8)2 + 7C3.(8)3 + ….. + 7C7.(8)7] – [9C0 + 9C1.8 + 9C2.(8)2 - 9C3.(8)3 + ….. 9C9.(8)0]

             = (7x8 + 9x8) + (21 x 82 – 36 x 82) + …..

             = 128 + 64(21 – 36)

               = 64[2 + (21 – 36) + …], viz. divisible by 64.

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