Sometimes a tricky SEO Interview question. Page rank is a Google algorithm. This is a metric for measuring the performance of the webpage submitted by webmasters to the search engines. Google discontinued revealing the page rank to the world.
SERP lists the pages that relate to any query made by the user. These results include both organic search as well as paid results. The results in the SERPs hold some position, and these are not just random positions.
The ranking positions are decided by the search engines using sophisticated algorithms, and page rank is one of them.
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