coolnaren wrote:

Hi please tell me what is wrong with this approach

let a -> average ( initial )

and n -> number of people ( initial)

(1430) / n - (1430)/ (n+45) = 9

but by solving i am getting very bad value of n.

kindly help

Your equation is correct and if you plug it into google you will get that n = 65.

Then you would need to divide 1430 by 65 to get answer (C).

But - this is an extremely complex quadratic equation.

If, like on this question, you find yourself in front of such a complex quadratic equation there is a very good chance that you've missed a shortcut. Look for it!

For example, look at the solutions using prime factorization above.

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