Q6 of 50 Page 26

The Bird problem in Class 8 (The lesson, Equations) can be slightly changed as follows.

One bird said:


“We and we again, together with half of us and half of that, and one more is a natural number”


Write the possible number of birds in order. For each of these, write the sum told by the bird also.


Find the algebraic expression for these two sequences.

Let the possible no of birds be x,


Therefore, according to given condition



Where N is any natural number.



⇒ 11x = 4N



Also, no of birds should also be a natural number, therefore N should be a multiple of 11, i.e. N = 11n for any natural no 'n'


Hence possible values of N = 11, 22, 33…


And possible values of x = 4, 8, 12, …


Algebraic expression for N is 11n


And


For x is 4n.


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