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3 years ago

Among the following, a perfect number a) 6 b)28 c) 625 d) 100

Mathematics

2 answers:

Gnesinka [82]3 years ago

8 0

<h3>Answer: A) 6 and B) 28</h3>

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Explanation:

By definition, a perfect number is one where the factors smaller than itself add to the number in question.

The factors of 6, smaller than 6, are {1,2,3}. We can see that 1+2+3 = 6. Therefore, 6 is a perfect number.

Similarly, 1+2+4+7+14 = 28 showing that 28 is also a perfect number.

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The factors of 625, that are smaller than 625, are 1,5,25,125. They add to 1+5+25+125 = 156. This isn't equal to 625, so 625 isn't a perfect number.

A similar issue happens with 100 as well. The smaller factors are 1,2,4,5,10,20,25,50, meaning we get a sum of 1+2+4+5+10+20+25+50 = 117, which is too large.

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The first four perfect numbers are: {6, 28, 496, 8128}

Verdich [7]3 years ago

6 0

Answer:

28 and 6

Step-by-step explanation:

List the factors (excluding itself):

6: 1, 2, 3,

28: 1, 2, 4, 7, 14

Add them up!

1+2+3=6

1+2+4+7+14=28

if they add up to the original number then the number is perfect.

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4 years ago

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dsp73

<h3>Solution:</h3>

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<h3>Answer:</h3>

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3 years ago

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Dmitriy789 [7]

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3 years ago

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arlik [135]

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3 years ago

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Vikki [24]

Answer:

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3 years ago

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Among the following, a perfect number a) 6 b)28 c) 625 d) 100​

Among the following, a perfect number a) 6 b)28 c) 625 d) 100