in reply to Number of listings per page

The low is N * P + 1. The high is N * (P + 1). So, if N is 15 and P is 0 (first page), you have 1-15. If P is 3 (4th page), then you have 46-60.

If your pages start from 1, then you have N*(P-1)+1 and N*P.

The way to solve these problems is to generate some sample results, then determining the pattern from them. Most mathematical equations are not written, then proven. You usually have a pattern, you map an equation to it, then you try and prove it for values beyond your pattern.

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