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Each time students visit the NRICH site there will be some activities which are 'live'. That means we are inviting students to send us their solutions and we will publish a selection of them, along with their name and school's name. If you'd like to know more about what we're looking for, read this short article.
The last day for sending in solutions to these live problems is Monday 27 November.
Can you explain the strategy for winning this game with any target?
Can you do a little mathematical detective work to figure out which number has been wiped out?