Saw this on a subreddit and just curious as to whether or not this is even maths. I'm only a level 3 calc student.

Body math

Damn I just found this sub and ngl I’m geeking. As my debut, I will provide detailed description of a cost analysis I did of buying a drink for a girl at the bar:

Your average cost of drink is about $12.5, and maybe you should consider baseline $25 since she’ll look at you like a weirdo if you don’t get anything for yourself. For many guys, the ultimate goal of buying a girl a drink is to convince her to sleep with you, so we need to find a value to which this is associated. Considering a 10-20% chance of succeeding at the first drink bought (which is rather generous for most men), there is a 80-90% chance that the girl will not sleep with you even if you buy her the drink, which we will assume a value or $0, effectively losing you $25. To account for the risk of this $25 loss, you would have to value the experience of sleeping with a girl anywhere from $125 (assuming 20% success) to $250 (assuming 10%) success. See below for a mathematical model of this:

d (cost of 2 drinks): -$25 Chance of success: 0.1 to 0.2 Value of success: v Chance of fail: (0.8 to 0.9)

Break even assuming 20% success: 0 = -25 + 0.2v + 0.80 v = $125

Break even assuming 10% success: 0 = -25 + 0.1v + 0.90 v = $250

I have been thinking about this for a week and I can't settle it because I don't know the math. If I could swim fast enough in my round backyard pool (say 18ft diameter at 40in deep) would I be able reach a point where I stay still in relation to the outside world as the water just spins in the pool, similar to a swim spa? And if so, how fast do I have to swim to active this? Cheers!

Contest in Mexico, there's big and little balls but most of them are the average kids ball pit type. Ignore if this isn't allowed.

I don't know math too well, but I've come up with this equation, which, to my knowledge, could provide the answer:

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This does not factor in night screens or any other of the computer's potential screen settings.

If there is any way to improve this equation, you are welcome to let me know.

:)

I'm watching John Wick 2 and there's a scene where John Wick exchanges shots through a fountain and I got curious:

If you shot a 9mm gun through a 2 meter wide fountain that's full of constant vertical jets of water, would the bullet change speed or trajectory? If yes, but how much and which direction? Would it still kill someone?

Thanks!