Recent comments in /f/explainlikeimfive

ActualGiantPenguin t1_iyc6cek wrote

Bear Stearns/Lehman Brothers weren't obscure at all, they just didn't generally offer consumer services except to high-net-worth individuals.

Similarly, Fannie Mae/Freddie Mac were founded to buy mortgages from banks, not to deal directly with consumers. They were both founded by the federal government (hence the similar names) but are private-sector entities.

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John_Vattic t1_iyc64td wrote

In your example, you're talking about if the 'agreed language' of math was different, the other answer would be correct. But, if the required answer for this scenario was 7, the actual calculation would be written differently.

It's like if you have a room full of people speaking English, and one dude who only speaks French. It's not that French is wrong, but they're not going to be understanding each other.

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SifTheAbyss t1_iyc5rk4 wrote

Because multiplication is a shorthand of repeated addition.

2 × 3 is 3 + 3, 3 × 5 would become 5 + 5 + 5, etc.

So 1 + 2 × 3 will give you 1 + (3 + 3). That 1 is just a simple number, it doesn't tell you anything about how many times you're supposed to add 3.

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Sereaph t1_iyc5dfu wrote

I'd like to delve deeper to clarify this concept. If we're talking PURELY numbers, PURELY mathematics, there IS NO order of operations. The math just *IS*.

For example, 1+2+3 = 6 doesn't happen left to right, right to left, or whatever order at all. 1+2+3 *IS* 6 and it *IS* 12-6 and it *IS* 18/3. All of these terms are just different ways of representing the number 6. They are equivalent, one in the same. Another way to think of it is that ALL the operations are done *at the same time*.

However, human beings aren't instant and we lose track of things all the time. Therefore, we devised the order of operations as an INTERPRETATION of how we observe the math actually works.

But I do want to clarify, this order of operations isn't just an "agreed upon standard" arbitrarily. It's following observed rules. The reason why multiplication comes before addition is because it is already a form of repeated addition.

7 + 3 x 4 is the same as 7+(4+4+4).

If we try it purely left to right, it doesn't make sense.

7+3x4 is not the same as 10x4 because the 3 is *modifying* the 4.

The 3 and the 4 are not separate terms. They are telling us that 4 happens 3 times (or that 3 happens 4 times). The 7 is just another term being added to the evaluation of 3 times 4. So we MUST evaluate 3x4 first.

Here's an illustration:

7 apples + 3 baskets of 4 apples. You don't add 7 apples to 3 baskets. You'd get what, 10 apple/baskets? That doesn't make sense. You add the baskets first (12 apples total), then add the extra 7 apples for a total of 19 apples.

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Spadeninja t1_iyc5chh wrote

Yes I get that

The question is though

When you have thousands of calculations, again in the instance of like a rocket launch, both are correct as long as everyone is on the same page?

And is the order between adding and multiplying is mostly meaningless as long as everyone is using those same calculations?

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peter3hg t1_iyc5ca8 wrote

It isn't really true to say that Ireland or Wales were what we would consider sovereign countries by modern standards before English rule/colonisation.

Ireland had a vast number of minor and major kingdoms with perhaps only Brian Boru being close to a true ruler over all Ireland, and that for less than 20 years in the early 11th century.

Similarly Wales have various kingdoms and only Gruffydd ap Llywelyn ruled a united Wales, again for a short period of time (less than 10 years) in the 11th century.

What both countries did have was a strong cultural identity across their various kingdoms, especially in contrast to the Anglo-Saxon and Norman ruled majority in England.

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BurnOutBrighter6 t1_iyc4yuq wrote

Both answers aren't right. On a test only one of those is right, and one is wrong. When you write:

1+2x3

That means "multiply two x three, then add one". There is only one right answer to this. It's 7. 9 is wrong.

If what you actually meant was add 1+2, then multiply by 3, than you have to write it as (1+2)x3, and then the only right answer is 9.

The rules we're talking about here are only about how to write the math so that it means what you intend it to mean (like multiply 2 by 3 then add 1, vs add 1+2 then multiply by 3). But for whatever you write, there's only one right answer.

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boring_pants t1_iyc4ffq wrote

We don't always do that.

If you have (1 + 2) x 3 for example, then you add before multiplying,.

It's just a convention to make it easier to read and write maths. We've agreed that if nothing else is specified, you multiply first. And if you want something else, you can toss a pair of parentheses around it to override that rule.

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nevbirks t1_iyc494y wrote

The easiest most simple explanation is that your body will turn up the heat to slow pathogens. The more you sleep the more energy conservation your body has to fight pathogens. Your body will use different nutrients to fight the bacteria. Your body has a type of cell called leukocyte that patrol the blood being on the lookout for anything abnormal. When depleted, you need protein to help replenish. That's why chicken noodle soup is so great. It's easy on the digestion system and has protein in it. Drinking lots of water helps clear our the kidney and liver allowing you to expel the pathogens.

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Half_burnt_skunk t1_iyc43kl wrote

The ribs of the human body are there to protect vital organs. Heart, obviously being the most important and lungs being the next. Those require major arteries to pump blood into them for them to function.

Your question is very vague, because there's many types of ammunition that come in different calibers, and different calibers of firearms have a variety of different ammunition. That's a big rabbit hole.

Let's assume someone is hit in the chest with a low caliber firearm with low grain bullets that aren't tipped in any special way. That bullet is passing through bone which in turn becomes its own projectile with force exertion towards your most vital organs.

If you throw in the mix, for instance, hollow-point ammunition, its main intention is to fragment when it hits the initial target. This sends many fragments of the bullet into the vital zone hitting more bones that fragment into the vital zone along side the bullet fragments.

That bullet is also-most likely-taking clothing and other foreign objects with it into the internal organs. All of these can cause a lot more complex operations and increase infection.

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Schnutzel t1_iyc41v6 wrote

Yes, megapixels is just resolution. It's just the number of pixels, in millions (mega = million). So a picture with a resolution of, say, 5312x2988, has a total of 5312*2988=15,872,256 pixels, which is just shy of 16 megapixels.

Videos usually have a much smaller resolution than still images, because they take up significantly more space. 4k resolution is 3840x2160 which is just 8 megapixels.

How manufacturers choose to denote resolutions is just a matter of marketing. Historically televisions were marketed using the numbers of lines on the screen (such as 360p, 720p, 1080p), then they switched to the number of columns (such as 4k, 8k). Meanwhile cameras just use megapixels.

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BurnOutBrighter6 t1_iyc3kd5 wrote

The math itself is fundamental. It would work no matter what convention we chose. The only arbitrary thing we're deciding on here is how to WRITE math so other humans know what you mean when there's more than one possibility.

(more than one possibility for what math you're trying to describe, NOT more than one way that the math itself could go!!!)

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