Fill in the missing stones across ten short pyramids. Every value stays between 0 and 20.
Number Pyramids within 20
Your Number Pyramid round
Ten pyramids with clear feedback. Take each stone at your own pace.
Number Pyramids within 20Question 1 / 10
0 / 10
Fill in the missing numbers. Each upper stone is the sum of the two stones directly below it.
204
Fill in the missing stones, then check your answers.
√
You completed all ten Number Pyramids.
You solved every pyramid stone by stone. You can practise the same round again.
How the rule works
Each upper stone is the sum of the two stones directly below it. For example, use two neighbouring lower stones to work out the stone they support.
Work from the clearest clue
Begin where two useful numbers meet. If the missing stone is above them, add. If a lower stone is missing, think about which number completes the known sum. Check one relationship at a time as the blank positions change.
Every completed stone in this round is a whole number from 0 to 20. You can correct any marked stone and check again before moving to the next pyramid.
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