Dealing the numbersβ¦
A row reads 7 Β· 3 Β· 5. The 7 and the 3 are side by side and add up to ten, so tap both and they go. Now the 5 has a new neighbour β whatever sits to the left of where the 7 was β because the cleared squares stop counting. That is the whole trick: every pair you take creates the next one.
On your own Β· 5β20 minutes Β· suggested from age 7 Β· free, no sign-up, plays in any browser.