This strip of tactile paving uses 80% of a paver on the right end of the first row and twenty per cent of a paver on the left end of the 2nd row.

I stared at this trying to think of a better way they could have done it. What I came up with is that they should have made the footpath about an inch wider, to be exactly 9 pavers wide.

Alternatively, if they had not used 20% of a paver on the left end of the second row, then I might not have noticed the eighty per cent of a paver on the right end of the 1st row.

You spelled one number but used an actual numeral for the description of the same information. That is more mildly infuriating than whatever you are upset about.