Puzzle 1
Frankie the Squirrel can find one acorn in 15 minutes and Glenn the Squirrel can find one acorn in 12 minutes. As autumn approaches, they both work all day and all night.
However, Alex the Squirrel is eating their collection! It takes Alex 20 minutes to eat an acorn, and Alex eats all day and all night long (and starts on yesterday's acorns).
How many extra acorns will there be at the end of a 24-hour day?
Puzzle 2
Start in the bottom left corner and move either up or right, one square at a time, adding up the numbers. What is the largest total you can make?
| 5 | 2 | 5 | 4 | 1 |
| 7 | 6 | 1 | 7 | 3 |
| 5 | 9 | 4 | 1 | 5 |
| 2 | 3 | 8 | 3 | 2 |
| 3 | 1 | 4 | 9 | 6 |
Note: this puzzle is not interactive, and the numbers cannot be clicked.
Puzzle 3
A Proof That 2 = 1. Let A = B:
A = B
multiply by A on both sides:
A x A = A x B
subtract B x B from both sides:
A x A − B x B = A x B − B x B
factorise:
(A + B)(A − B) = B(A − B)
divide by (A − B) on both sides:
(A + B) = B
replace A with B:
B + B = B
factorise:
2B = B
divide by B on both sides:
2 = 1
Where lies the flaw in the logic?
Puzzle 4
What is the smallest positive integer which …
… when multiplied by 3 gives a number consisting of only 4's?