The case notes
What X and V mean
Digits separated by an X add to 10. Digits separated by a V add to 5. Watch a worked example, then try the idea in a puzzle.
Put it into practice
Two marks, two totals
These letters sit between pairs of Sudoku cells. An X and a V give us two different totals.
X means sum to 10
An X means its two neighbouring digits add to ten. Here one cell is four, so the other must be six.
V means sum to 5
A V means its neighbours add to five. Two is already here, leaving three for the cell beside it.
X: 10 · V: 5
Four and six make ten. Two and three make five. When you see a letter, check the pair on either side.
Read the transcript
These letters sit between pairs of Sudoku cells. An X and a V give us two different totals. An X means its two neighbouring digits add to ten. Here one cell is four, so the other must be six. A V means its neighbours add to five. Two is already here, leaving three for the cell beside it. Four and six make ten. Two and three make five. When you see a letter, check the pair on either side.
