Krystyna has some raisins. After giving some away and eating some, she has 16 left. How many did she start with?
CEMC Pascal
Solution
Working backwards, Krystyna had 36 raisins before eating 4, and 54 raisins initially.
Want a route through all this instead of an archive? The track
puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.