dnbguy

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TROPHY CASE


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H.R. 5002: To suspend temporarily the duty on Benzamide, N[[[3,5 Dichloro-2-fluoro-4-1,1,2,3,3,3-hexafluoropropoxy)phenyl] amino]carbonyl] 2,6 difluoro - (9Cl). by congressbotin watchingcongress

[–]dnbguy 1 point2 points ago*

This is also known as novifluoromon. It is used as the active ingredient in new termite bait being manufactured by Dow AgroSciences (see here). Dow AgroSciences is headquartered in Indianapolis, inside the newly redistricted 5th district represented by Rep. Burton.

Simulating a random point in a circle. by AlienRaperin learnmath

[–]dnbguy 2 points3 points ago

This isn't exactly right. You need to take the square root of r.

Simulating a random point in a circle. by AlienRaperin learnmath

[–]dnbguy 0 points1 point ago

Generate two uniform random numbers, t in [0, 2*pi) and a in [0,r] (with r = the radius of the circle). Let b = sqrt(a). (b cos t, b sin t) is a point uniformly chosen within the circle you chose.

Is playing the lottery statistically worth it? (Math related) by kashifrin answers

[–]dnbguy 8 points9 points ago

Your brother correctly computed the odds of winning the jackpot. It is 1 in 175,711,536 to be precise. This looks too good to be true, and it is. There are a couple of issues here.

There are two options for accepting the jackpot of a game like Mega Millions. One option is to have a set sum of money paid to you every year for 26 years. For the most recent jackpot, you could have approximately $24.64 million paid to you per year. $24.64 million x 26 = $640 million, the listed jackpot. However, $24.64 million today is worth more than $24.64 million tomorrow, which is worth more than $24.64 million in one year, which is worth more than $24.64 million in 26 years. You can also elect to take the entire jackpot in one lump sum, today. The most recent value for the lump sum is $462 million. If you add in taxes, you only see about $350 million of it.

Taking this all into consideration, it still looks like a good deal, right? Unfortunately, there is one more issue. What happens if more than one person wins? Mega Millions isn't going to give each winner their own jackpot, they are instead going to split the jackpot among each of the winners. To find the expected number of winning tickets there are, multiply the number of tickets sold by the probability of a ticket winning. We have the probability of a ticket winning from above, 1/175711536. I read somewhere that about 550 million tickets were sold the past few days. Do the multiplication, you would expect that about three tickets would be winners; lo and behold, there were three winners. The jackpot gets divided into three parts, and all of a sudden it is not as dramatically big as it once was.

In conclusion, the best strategy to game the system is to try and drive down the number of total tickets sold.

Solving trigonometric identities! by MahoganyDeskin cheatatmathhomework

[–]dnbguy 0 points1 point ago

'Cuz if you divide by 0 then the world breaks.

Don't break the world! But what about pi? Also, is there another solution to setting cscx = 0 in [0, 2pi)?

Solving trigonometric identities! by MahoganyDeskin cheatatmathhomework

[–]dnbguy 0 points1 point ago

So then would the cscx portion be equal to pi over 6?

That is one solution

And the tanx equal to 0 and pi?

Be careful

[Probability] Law of rare events by thecircleofredditin cheatatmathhomework

[–]dnbguy 1 point2 points ago

Think I follow now:

There are N points you have uniformly distributed on the surface of a circular disk with radius r. For each of the N points, we can introduce an indicator variable, Z_i. Z_i = 1 if point i is in the small circle of radius 1 in the center, and 0 otherwise. Since we have a uniform distribution, the probability that any point i is in that small circle is equal to the ratio of areas, 1/r2. Therefore, the Z_i are all Bernoulli random variables with parameter 1/r2. The Z_i are all independent of each other as well. If we add up all of these indicator variables, we get X, the # of points in the small circle of radius 1 in the center.

Now, the sum of a series of independent identically distributed Bernoulli random variables is a binomial random variable. The two parameters for a binomial random variable are the number of points, N, and the probability of success, in this case 1/r2. As N and r both go to infinity, we have a lot of points with not much probability of success...

BUT! The expected value of X, our binomial random variable, is N * 1/r2 = N/r2. This is a constant. As it turns out, if N is large and 1/r2 is small, we can approximate binomial random variables very well with a Poisson distribution with parameter N/r2.

Solving trigonometric identities! by MahoganyDeskin cheatatmathhomework

[–]dnbguy 0 points1 point ago

You have to be careful when factoring out. You can set one term equal to 0 and solve, but make sure the answer you get makes sense in the other term!

sinx is 3/(2 X sqrt(3)), yes. To rationalize the denominator, multiply the top and bottom by sqrt(3). That becomes (3 X sqrt(3))/(2 X 3). It simplifies nicely.

[Probability] Law of rare events by thecircleofredditin cheatatmathhomework

[–]dnbguy 1 point2 points ago

Not sure I understand where you are getting your Z_i from. Have you heard of the Poisson distribution?

ELI5 Why do my eyes hurt from bright lights when I wake up, but then they "get used to" the light? by RafiTheMage447in explainlikeimfive

[–]dnbguy 0 points1 point ago

Ever notice the black circles in the middle of each of your eyes? Those are called your pupils. The part of your eyes that have colors are called your irises. Light enters your eyes through the irises. The pupil blocks light from getting to your iris - think of it like a shield. In environments where there is very little light, like nighttime, your pupil gets very small, allowing as much light as possible to hit your iris. In environments where there is a lot of light, like daytime, your pupil will get larger to protect your eye (too much light will damage your eyes!). It takes some time for the pupil to change sizes, though, so if you turn the lights on after being in the dark for a while, it will hurt!

Fun experiment, late at night, after being in darkness for a little while, go into your bathroom, turn the lights on, and look in the mirror at your pupils. It's fun!

If the President and Vice-President elects both die before inauguration, who becomes President? by enad58in answers

[–]dnbguy 2 points3 points ago

Boehner would still be speaker up until the new Congress starts at the beginning of the year (usually around January 3rd). Once the new speaker is sworn in, they join the line of succession.

ELI5: Can someone please explain the election process in the US? by sweepysoilin explainlikeimfive

[–]dnbguy 0 points1 point ago

Mitt Romney won the Republican caucus in Iowa on the 3rd, and the Republican primary on the 10th. There were also Democratic versions of the caucus and primary, taking place on the same days as the GOP version. Barack Obama won these.

It is hard to compare the turnout for the primaries to the turnout for the general election. This year, there are competitive primaries for the GOP nomination, whereas the Democratic primaries are little more than a formality for Obama. So, you would expect more people to vote in the Republican primaries than in the Democratic primaries; this doesn't necessarily mean that the Republican will win.

ELI5: Can someone please explain the election process in the US? by sweepysoilin explainlikeimfive

[–]dnbguy 0 points1 point ago

In all but two states (Maine and Nebraska), each state is winner take all: if you win the state, you are entitled to all of the electoral votes in that state. In the case of Alabama, some people voted for the Obama/Biden ticket, but more people voted for McCain/Palin.

ELI5: Can someone please explain the election process in the US? by sweepysoilin explainlikeimfive

[–]dnbguy 1 point2 points ago

Electors are usually either members of the state legislature, former members of Congress, or party activists. You can find a list of all of them here. On election day, you are correct, the general public is officially voting for the slate of electors for that candidate. Some states list the electors on the ballot, most just list the presidential/vice presidential nominees. The electors meet at their respective state capitals about a month after the election, on the first Monday after the second Wednesday in December. It is at this time that they cast their ballots for president and vice president.

The goal of the primaries for each party who they want to represent them in the general election, yes. People can vote in either the Democratic primary or the Republican primary, but not both. If you were a Democrat who could also vote in the Republican primary (or vice versa), you could vote for someone crazy and try and sabotage their nominee!

ELI5: Can someone please explain the election process in the US? by sweepysoilin explainlikeimfive

[–]dnbguy 0 points1 point ago

Senators and representatives are directly elected, yes. Representatives have always been directly elected, senators have been since the 17th amendment was adopted in 1913. Prior to that, senators were chosen each individual state's legislature.

ELI5: Can someone please explain the election process in the US? by sweepysoilin explainlikeimfive

[–]dnbguy 2 points3 points ago

The method for selecting the electors for the electoral college differs from state to state. Some states do just what you described, placing a list of names on a primary ballot and having voters select which ones they want. Other states nominate their electors at the state convention right before the election. The other option is to have the campaign of the person running for president pick the slate (this is how it is done in Pennsylvania). I don't know which method California uses.

The electors are completely separate from the members of the Senate and House of Representatives. In fact, the Constitution states that electors CANNOT be in the Senate, the House, or an appointed position in the federal government ("holding an office of trust or profit").

Sources: Electoral Vote Constitution

X is a random variable and E[X]=Var(X)=20. Is it possible to have P(0<X<40) = 7/8? by w3lcome_homein learnmath

[–]dnbguy 1 point2 points ago

Chebyshev's inequality states that no more than 1/k2 of a distribution's values are more than k standard deviations away from the mean. 0 and 40 are 201/2 standard deviations away, so no more than 1/20 of the distribution can be outside this interval. So, P(0 < X < 40) >= 19/20 > 7/8.

tl;dr No.

Football newbies, ask us anything! by NFL_Modin nfl

[–]dnbguy -1 points0 points ago

Same rule applies. See here, you'll notice there are two players lined up behind the players on the end of the line facing outwards. Most field goal formations look something like that.

help with m^13 mod 10 = m mod 10 by PingofDingin cheatatmathhomework

[–]dnbguy 1 point2 points ago

For two things to be congruent mod 10, they must also be congruent mod 2 and mod 5. Use Fermat's Little Theorem based on that.

Help with a combinatorics question.. by Aeckz-in learnmath

[–]dnbguy 1 point2 points ago

sorry, this has been archived and can no longer be voted on

This isn't exactly right, you are double counting. If you pick guy 1, girl 1, and then guy 2 for your "wild card", that is the same as picking guy 2, girl 1, and guy 1 for your "wild card".

Help with a combinatorics question.. by Aeckz-in learnmath

[–]dnbguy 1 point2 points ago

sorry, this has been archived and can no longer be voted on

I'm afraid not. How many different gender combinations are there? Then, for each gender combination, how many teams can you create?

Also, since the team members are all indistinguishable, you should be using combinations, not permutations.

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