Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [problem-solving]

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.

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.

4495 questions
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partition of $\mathbb{Z}$ into finitely many translation

Few days ago, a friend of mine gave me this problem : Let $X \subset \mathbb{Z}$ and suppose that $a_1, a_2, \cdots, a_n$ are integers such that $X+a_1, \cdots, X+a_n$ is a partition of $\mathbb{Z}$. Prove that $X+p=X$ for some nonzero integer…
Ajat Adriansyah
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Time and distance problem

A train starts from Jammu for Srinagar at 13:30 and reached at 17:30.Another train starts from Srinagar at 15:30 and reaches Jammu at 19:00.At what time both train will meet??. I have solved this problem using traditional approach, but I need some…
Shaddy
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How do you work out the angle in this square?

I have labelled all the angles that I can work out. But I can't think of any other way to find the other angles without being 100% sure. Thank you! P.S. I have attached the official question - I have scribbled all over it with lines and therefore…
itshanks
  • 532
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How does one establish a path of least resistance when solving equations?

For certain systems of equations, it is obvious what the easiest way to organize and manipulate the equations should be. For instance, $$y = 10x + 5$$ $$2x + y = 125$$ So you take the first equation and plug it into the second…
Stan Shunpike
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Finding the number of multiples

I have recently been doing problem solving in math, and I came across this problem: Determine the number of positive multiples of $6$ or $9$ or both, less than $1000$. I appreciate any help. Thanks!
Mathinator06
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Odd and even coins

Two friends are playing a coin game. You need to give to your friend, one coin that has an even value and another coin that has an odd value. For example, a dime would be the even value since its value is $10$ and a nickel could be the odd…
sharonnicole116
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Water & salt liquid

If I'd have an $500$ ml bottle of water and it would have $1\%$ salt, how much I would need to add water to make it, lets say $0.3\%$? I cannot find the way to figure this problem. Could anyone provide the formula to solve this? Regards, TuukkaX.
user276849
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How to decompose $z^8-1$?

I want to express $z^8-1$ as a product of two linear factors and three quadratic factors, where all coefficients are real and expressed in a non-trigonometric form. I know…
Rescy_
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10 year old homework ABCDE +BCDE =

Kids maths homework - ABCDE + BCDE + CDE ______ 74915 We're told A = 7. I don't even know how to go about working this out. Help?!
user269433
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How many columns in a grid of arbitrary width, with minimum and maximum allowed column widths?

In a grid of variable width, with a variable number of columns having a minimum and maximum allowed width, how can I calculate the number of columns for any given grid width so they fall within the minimum and maximum allowed column width? Phrased…
Parker Ault
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A mathematics competition had 9 easy and 6 difficult problems

A mathematics competition had 9 easy and 6 difficult problems. Each of the participants in the competition solved 14 out of 15 problems. For each pair consisting of an easy and a difficult problem, the number of participants who solved both those…
0327
  • 337
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$(a+b+c\cdots)\neq(a^{2}+b^{2}+c^{2}\cdots)$ given all distinct values for the variables?

Please note that the solution must not require more equations to solve as do the variables increase. Apparently, $(a+b+c\cdots)\neq(a^{2}+b^{2}+c^{2}\cdots)$ seems pretty obviously to be true given that all variables $a,b,c\cdots$ are distinct…
XenoGraff
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How to get from: $a^2 - a + 1 = 0$ to $a = \frac{1}{2}(1\pm\sqrt{1+4})$

Given that $a^2 - a + 1 = 0$, my book says: Therefor $a = \frac{1}{2}(1\pm\sqrt{1+4}).$ I have forgotten all the theory behind this.
Gineer
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What area can this question be categorized into?

In a game of 12 players that lasts for exactly 75 minutes there are 6 reserves who alternate equally with starting players. It means that all players, including reserves, are in the game for exactly the same amount of time. How long is this? 5…
OyWSONN9
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Problem leading equations

The question is : "A and B begin to play with 60$ each. If they play till A's money is double B's, what does A win?" Now i tried to solve it like they both have 60\$ each, then A got his money doubled than B so he must have got 120\$ so i think that…
user20078
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