Challenging Math Problems (Or not)

[binary010101]

Assuming a range of all possible numbers, shouldn't there be an infinite number of permutations?

[gh]

Don't remember what this was from, but it might have been something from NYCIML. Find the next term in the sequence:

[EpicFailOlympian]

Don't remember what this was from, but it might have been something from NYCIML. Find the next term in the sequence:

2?

[blue cobra]

Don't remember what this was from, but it might have been something from NYCIML. Find the next term in the sequence:

28?

I kind of took a bit of a stretch to get that though.

[EpicFailOlympian]

how did you get that?

[blue cobra]

Don't remember what this was from, but it might have been something from NYCIML. Find the next term in the sequence:

28?

I kind of took a bit of a stretch to get that though.

how did you get that?

I don't know if it is right, but I saw that for the first digit, the pattern seems to be that you subtract, going left to right. That would mean 7-4 gives you 3, then 4-3 gives you 1, so 3-1 would then give you 2. Where I feel I took a bit of a guess (supposing I'm not entirely wrong) is with the second digit. I added those, but only used each once, then copied them to the next number. So 2+2=4, so the next 2 numbers would have 4 as their second digit, and then 4+4=8.

[lllazar]

Is it 28?

O ****, nice Blue Cobra

But ya, i couldn't find any patterns in the whole numbers themselves, broke it down.

[lllazar]

Here's one that tripped me up for a few days:

Find the next number in the sequence and the solution

[blue cobra]

Here's one that tripped me up for a few days:

Find the next number in the sequence and the solution

53

You subtract the second digit of the number from the first digit, and then subtract this from the whole number to get the next number in the sequence.

[RandomPerson]

Nice job Blue cobra, I think you got it.

I just stumbled across this, I hope no one minds If I post it.
Its technically a word problem as much as a math one, but it is heavily based in math, and all the solutions I've seen are in math. Anyways, if you guys don't like it, feel free to ignore:

"You are trapped in a prison and the guard decides to play a game. If you win, you will be allowed to leave. But if you lose, you die. The guard says that he is thinking of number 1, number 2, or number 3. You are allowed to ask one question to find out which of these three numbers the guard has in mind. However, the guard will only answer with a “yes”, “no”, or “I don’t know”. What should you say to the guard?"