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lord [1]
3 years ago
11

Prove if the sum of the digits of a 3 digit number n is divisible by 9, then n is divisible by 9.

Mathematics
1 answer:
beks73 [17]3 years ago
6 0

n=100x+10y+z\\x+y+z=9k,k\in\mathbb{Z}\\\\n=99x+9y+x+y+z\\n=99x+9y+9k\\n=9(11x+y+k)

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4.

Step-by-step explanation:

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Answer:

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Step-by-step explanation:

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8 0
3 years ago
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Minchanka [31]

Answer:

Explained below.

Step-by-step explanation:

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2 years ago
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Alex777 [14]

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