# explain the whole solution especially that part in which we put n=23 we do we do that

In first step we put the formula of sum of

*n*for two APs.

In second step both 2 get cancelled.

And formula of

*n*terms for two APs.

We take

*n*= 23 to compare with equation (1), so that both become exact same.

This is HIT and TRIAL method for solving these type of questions.

Regards

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