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Write an expression for the sum of 1 and twice a number n. If you let n be any odd number, will the result always be an odd number?

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Question

Write an expression for the sum of 1 and twice a number n. If you let n be any odd number, will the result always be an odd number?

Sum
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Solution

Let the number be n

So, according to the statement, the expression can be written as = 2n + 1

Yes, the result is always an odd number, because when a number becomes multiplied by 2, it becomes even and addition of 1 in that even number makes it an odd number.

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Chapter 10: Algebraic Expressions - Exercise [Page 328]

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NCERT Exemplar Mathematics Exemplar Class 7
Chapter 10 Algebraic Expressions
Exercise | Q 96. | Page 328

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