An ancient Egyptian scribe is recording the arrival of 25 sacks of wheat into the Pharaoh's royal granary. For every single sack carried inside by the workers, the scribe carves one stroke onto a clay tablet. To make the final count easier to read for the high priest, he organises the strokes into simple groups of five.
(i) How many total marks (symbols) will the scribe carve to count the 25 sacks of wheat?
(ii) Draw how the marks would look on the clay tablet using the scribe's five-grouping method.
(iii) If a final boat arrives at the dock with 5 more sacks of wheat, how many total marks will the scribe have carved on his tablet?
(iv) The scribe's method of recording demonstrates which fundamental counting principle?