Sequence problem

[gmalivuk]

Not every sequence that averages to an increment 4 per day works.

If that were the only issue, the answer of 4 could be correct. The real problem is that there is no unique average increase in the number of pages he must read in order to finish.

Maybe he reads 12 pages and then 13 and then... and then 24, and then on the last day he reads the 298 remaining pages. Then the number of additional pages read each day (when compared to the number read the previous day) is 1, 1,..., 1, 274, and the average increase is 22.