2024

It’s a tradition on this site to publish some puzzles related to the new year. Happy New Year!

1) a^2 – b^2^**/*****
Find 2 numbers a and b such that a² – b² = 024.

2) 1…9^***/*****
Use the digits 1, 2, 3, … 8, 9 exactly to make 2024. You can use all arithmetical operations, including brackets, but don’t change the sequence of the digits.

They year 2024 is a remarkable year. Several sums can be made with the digits:
2+2=4
2*2=4
2^2=4
2+2=4+0

3) 2024 sums ^*/*****
a) What is the next year with the same four digits?
b) How many years exist with these 4 digits?
c) What is the next year with digits a,b,c, and d such that a+c=d?
d) How many years abcd did we already have in this millenium such that a+c=d?

New puzzles are published at least once a month on Fridays. Solutions are published after one or more weeks. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to 5 stars. You can check your solution here.