# Tagged Questions

Use this tag when you want to determine the thinking that is needed to solve a certain type of problem, as opposed to looking for a specific answer to a question.

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### Numerically solve an equation using Python

How could I (numerically) solve this equation for $\alpha$ given $x_i$ (these are known) ? $\sum_{i=1}^N\frac{1}{x_i-\alpha} = \frac{2N}{\sum_{i=1}^{N}(x_i-\alpha)^2}\sum_{i=1}^{N}{(x_i-\alpha)}$ In ...
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### Why we not check conditions while solving questions?

Note:Down ward problem is just an example to express my question(I know the both solution of problem are insufficient but the first solution is in my 10+2 book and second one is mine which is ...
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### Find two fractions such that their sum added to their product equals $1$

This is a very interesting word problem that I came across in an old textbook of mine. So I managed to make a formula redefining the question, but other than that, the textbook gave no hints really ...
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### When Ben added $2$ of $4$ together repeatedly, he got $4$ consecutive numbers. Show that either $3$ or $1$ of his $4$ numbers were even

Ben had $4$ numbers: $a, b, c,$ and $d$. $a+c=e$ $a+d=f$ $b+c=g$ $b+d=h$ $e,f,g,h$ are consecutive. Prove that either $1$ or $3$ of $a,b,c,d$ were even
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### What are the $5$ different combinations of $4$ numbers that can add to $8, 9, 10$ or $11$? [duplicate]

There are $5$ combinations of $4$ numbers from $1-9$. If you write these on two coins, so there are $2$ numbers on each coin. Then you flip the coin. The sum of the two numbers add to $8,9,10,$ or ...
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### How many different ways can you order a binary code (only 1s and 0s) if there is 5 of one and 6 of the other?

If you have 6 0's and 5 1's, like in binary, how many different ways can you order them? Also, there is a popup saying that the question appears subjective. Is it?
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### How can the policeman catch the gangster?

I try to solve the following problem (Moscow Mathematical Olympiad, 1978) There is a town with six streets: four sides of a square and two its middle lines. Policeman tries to catch a gangster. If ...
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### Given $f(x)=x^2-4x+3$, find the points on the curve $y=f(x)$ where the tangent to the curve passes through -6.

Given $f(x)=x^2-4x+3$, find the points on the curve $y=f(x)$ where the tangent to the curve passes through $(0,-6)$. State the equations of the tangents at these points. Hi everyone, I tried to find ...
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### Sum of correlated random variables and the Law of Large Numbers?

Suppose I have a random variable $X$ which can take values on the set $\mathcal{X}=\{1,2,\dots,m\}$ and $X$ is drawn according to the given probability mass function ...
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### How to debug math?

May seem strange as I'm good in programming, but I just started diving into math. ATM I'm learning combinatorics at Khan Academy, and here's an example of a question that I struggled with (that's not ...
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### Three screw problem

There are three identical screws with diffrent amounts of nuts and disks on them. Here is the problem picture: How do you calculate the weight of a screw, the nuts and the disks?