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प्रश्न
128 ∈ {y | the sum of all the positive factors of y is 2y}
विकल्प
True
False
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उत्तर
This statement is False.
Explanation:
Given that: 128 ∈ {y|the sum of all positive factors of y is 2y}
∴ Factors of 128 are 1, 2, 4, 8, 16, 32, 64 and 128.
Sum of all the factors = 1 + 2 + 4 + 8 + 16 + 32 + 64 + 128
= 255 ≠ 2 × 128
Hence, the given statement is false.
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