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Sunday Afternoon Maths LXV

 Posted on 2018-05-13 

Cryptic crossnumber #1

In this puzzle, the clues are written like clues from a cryptic crossword, but the answers are all numbers. You can download a printable pdf of this puzzle here.
1 2
3 4

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Breaking Chocolate

You are given a bar of chocolate made up of 15 small blocks arranged in a 3×5 grid.
You want to snap the chocolate bar into 15 individual pieces. What is the fewest number of snaps that you need to break the bar? (One snap consists of picking up one piece of chocolate and snapping it into two pieces.)

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Square and cube endings

Source: UKMT 2011 Senior Kangaroo
How many positive two-digit numbers are there whose square and cube both end in the same digit?

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If you enjoyed these puzzles, check out Sunday Afternoon Maths LXVII,
puzzles about taxicab geometry, or a random puzzle.
© Matthew Scroggs 2019