Random Math Problem Generator

[Dona Vansoest]

Howto use Javascript to ask the user random math questions? If the user answers correctly, the program is suppossed to say Correct! If the answer is wrong, the program is suppossed to say FALSE! I'm thinking of using if and else statements, but I just don't know how. Also, i'm thinking of making the program ask different random number ADDITION questions to the user 5 times. AT the end, the program gives the user a rating, such as 4/5 questions answered correctly! Random number range: 1-10

I've left division off here, as the rest assumes integers and you'd have to change your initialisation to prevent a division from producing fractional values. The straightforward way would be to initialise a multiply, then swap the result and a.

I think you are going about this in the wrong direction. Why do you need to store the operator as a string? Why have all these separate random instances? At the end of the day you need to randomly generate a math problem right? And you have to determine if the user gets the answer correct or not.

We have already generated the question so we dont need the number variables anymore, but just so you are aware, the Convert calls you do are completely unnecessary. Console.WriteLine() will automatically call ToString() on its arguments. And every single thing in C# can have .ToString() called on it since its a member of object and everything in C# inherits from System.Object:

I would like to make a math quiz/game for my kids. I'm going to use an Arduino, a display of some sort and a keypad. Also some lights and sounds to make it fun for children. The game should include at least addition, subtraction and multiplication. I've searched the net but I cannot find this sort of projects built by anybody else.

Sounds can be expensive to produce. However, I have found you can easily include the sound from the series of sound machines you can get. I used the standard one to get 16 quality sound effects in this project:-

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There are others with different sounds.

If you want there to be some randomness, then you can generate 2 random numbers and a random sign and let the Arduino calculate the result. This will work fine for simple arithmetic and algebra. If you're looking at generating random high order differential equations, that might be a tad difficult.

Each function would have a similar signature, and would provide a textual question,and a numeric answer. I'd probably pass in a pointer to a char array to receive the question as a c-string, and provide the expected answer as the function return value. Each function would generate random numbers for the values used in the question, calculate the answer, and format the question as a string. I'd expect each function to be 2-3 lines of code.

I'd use a random number to select which type of question to ask and a switch statement to invoke the corresponding question generator, then some common code to ask the question and check the answer (in a loop if you're going to allow multiple guesses, or keeping scores etc). (I would consider using an array of function pointers instead of the switch, but the switch is more straight forward.)

I know the internet is full of these games and my kids have them on iPhone as well, but that's not the point. The point is to learn programming by building something that I find interesting. Also, to show my kids that we can build electronics ourselves, not just consume.

It depends upon the age of your kid.. However, i used to tell them the names of the components i am using in assembling of my PCB. They got curious and want more information...

You want to learn them programming or you want to learn them mathematics?

The easy and medium ones are pretty straight-forward. Random ints separated by random operators, nothing crazy here. But I'm having some trouble getting started with something that could create one of the hard and harder examples. I'm not even sure a single algorithm could give me the last two.

Also note that I will have to evaluate those expressions. This can be done either after the expression is generated, or during its creation. If you take that in consideration in your answer, that's great.

You are looking to randomly generate words (algebraic expression) from a given language (the infinite set of all syntactically correct algebraic expressions). Here's a formal description of a simplified algebraic grammar supporting only addition and multiplication:

Here, E is an expression (i.e., a word of your language) and I is a terminal symbol (i.e., it's not expanded any further) representing an integer. The above definition for E has three production rules. Based on this definition, we can randomly build a valid arithmetic as follows:

I assume you would choose to represent an expression with an interface Expression which is implemented by classes IntExpression, AddExpression and MultiplyExpression. The latter two then would have a leftExpression and rightExpression. All Expression subclasses are required to implement an evaluate method, which works recursively on the tree structure defined by these objects and effectively implements the composite pattern.

Note that for the above grammar and algorithm, the probability of expanding an expression E into a terminal symbol I is only p = 1/3, while the probability to expand an expression into two further expressions is 1-p = 2/3. Therefore, the expected number of integers in a formula produced by the above algorithm is actually infinite. The expected length of an expression is subject to the recurrence relation

where l(n) denotes the expected length of the arithmetic expression after n applications of production rules. I therefore suggest that you assign a rather high probability p to the rule E -> I such that you end up with a fairly small expression with high probability.

first of all I'd actually generate the expression in postfix notation, you can easily convert to infix or evaluate after generating your random expression, but doing it in postfix means you don't need to worry about parenthesis or precedence.

The parentheses in the "hard" expression represent order of evaluation. Rather than trying to generate the displayed form directly, just come up with a list of operators in random order, and derive the display form of the expression from that.

Update: here is an algorithm in Perl to generate the display form. Because + and * are distributive, it randomizes the order of the terms for those operators. That helps keep the parentheses from all building up on one side.

I would use trees. They can give you great control on the generation of the expressions. E.g. you can limit the depth per branch and width of each level separately. Tree based generation also gives the answer already during the generation, which is useful if you want to ensure that also the result (and subresults) are hard enough and/or not too hard to solve. Especially if you add division operator at some point, you can generate expressions that evaluate to whole numbers.

Parsers start with a stream of terminals (literal tokens like 5 or *) and try to assemble them into nonterminals (things composed of terminals and other nonterminals, such as number or op). Your problem starts with nonterminals and works in reverse, picking anything between the "or" (pipe) symbols at random when one is encountered and recursively repeating the process until reaching a terminal.

A couple of the other answers have suggested that this is a tree problem, which it is for a certain narrow class of cases where there are no nonterminals that reference themselves directly or indirectly through another nonterminal. Since grammars allow that, this problem is really a directed graph. (Indirect references through another nonterminals count toward this as well.)

There was a program called Spew published on Usenet in the late 1980s which was originally designed to generate random tabloid headlines and also happens to be a great vehicle for experimenting with these "reverse grammars." It operates by reading a template that directs the production of a random stream of terminals. Beyond its amusement value (headlines, country songs, pronounceable English gibberish), I've written numerous templates that are useful for generating test data that's ranged from plain text to XML to syntactically-correct-but-uncompilable C. Despite being 26 years old and written in K&R C and having an ugly template format, it compiles just fine and works as advertised. I whipped up a template that solves your problem and posted it on pastebin since adding that much text here doesn't seem appropriate.

gniruT is an application that writes math questions and solves them. This math question generator has been built around the gniruT application and covers subjects from addition, subtraction, multiplication, division, patterns, conversion, sorting, rounding and algebra to polynomials and calculus.

The models behind the application operate with variable boundaries and every point inside that created space has a variable entropy. So what that means is it will fully explore that little universe, every range, border case and edge boundary without bias to generate the questions and answers. Because of this, the models generate some really interesting questions which force us to think more deeply about what is being asked and gives students a taste of the intellectual adventure that mathematics can be.

SUP people. I'm doing random number generator but it is like lottery. With one press on the button i generate 7 diffrent numbers. My problem is how to make them that there are diffrent number and there cant be any numbers that are the same. Thanks for responds!

That is my designer... I hope u can understand my language. I'm from Slovenia but i think if u do this often u dont need translate... Text for label its just title...but just in case u need translate:

število=number

prvo=first

drugo= second,.....

generiraj števila=generate numbers

ListAddon Extension This extension allows for doing more things with App Inventor Lists. I made this extension with Kodular IDE. ? Current version: 1 Release date: 2019-04-21T21:00:00Z (UTC) Required permissions: none Min API required: N/A ...

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