A new December and a new bunch of puzzles from mscroggs.co.uk.

Part of the mystery this year is this formula:

• Santa tells his three-digit number to the first elf.
• The first elf subtracts her three-digit number then multiplies by her one-digit number. She tells her result to the second elf.
• The second elf subtracts his three-digit number then multiplies by his one-digit number. He tells his result to the third elf.
• The third elf subtracts their three-digit number then multiplies by their one-digit number. Their result is a five-digit number that is the code to unlock the warehouse.

It is tempting to try to write this as pure math. I don’t know at this point whether that actually helps.

• (aaa – bbb)*c = x
• (x – ddd)*e = y
• (y – fff)*g = hhhhh