Coverage changes with read count and read length over the same toy genome length. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
Coverage is a read-base budget
Genome length stays 1000 bases. The scan changes read count and read length before dividing by that same genome length.
coverage=genome lengthreads⋅read length
Read count and read length both change coverage
The first two rows isolate read count. The final row keeps the same read count but increases read length.
reads102020length100100150coverage123
The final row reaches three-times coverage
For the rendered row, 20 reads of length 150 over 1000 bases gives 3 x.