Questions tagged [mathematics]

A puzzle related to mathematical facts and objects, whose solution needs mathematical arguments. General mathematics questions are off-topic but can be asked on Mathematics Stack Exchange.

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“Infinite Steps” [closed]

Three Mathematicians standing on infinite ladder on step number 35, 192, 227 respectively. Everyone has same two secret formula, based on current standing position(step Number) one of the formula ...
213 views

Using numbers form a number

Using 7,8,9 and basic mathematical operations form the number 327600. Use every digit exactly once. Note: Allowed Operations: $+,-,/,*, {}^{\displaystyle\large\hat{}} ,!,\sqrt{}$
145 views

A Sweetematical Puzzle [closed]

There are $n$ sweets in a bag, $6$ of the sweets are orange. The rest of the sweets are yellow. Hannah takes a random sweet from the bag She eats it. Hannah takes another random sweet from the bag ...
129 views

Be Quick and Calculating..Take Four Shots

To Target Sum of 100 Exactly . By shooting the right different numbers in four shots summing upto 100.
123 views

Prime Sequence…a little bit Unusual about the Missing Members

What are the Missing Members in this Prime Series? what is the Significance of this Sequence? $19$, $17$, $13$, $?$, $?$, $3$, $2$
177 views

In a certain city, there are only two companies (called Company A and Company B), that manufacture computer mice. The computer mice from Company A last $x$ hours before needing to be recharged, ...
578 views

What's the pattern?

I went to a library and found a book which contained puzzles. I found this puzzle, and decoded it. I showed it to my friends, and they couldn't figure out. I then posted it on this website... Find ...
104 views

What number should be placed in that last slot? [closed]

I came across a very difficult puzzle. What number should be placed in that last slot? I only know 16 is not the correct answer, because 11 is before 10.
367 views

A party of jealous guys

I was really happy for the fact that I won the inter-galactic best magician award. So I decided to throw a party of $n$ people (excluding me). The people who came to that party was jealous, really ...
140 views

How long time does it take an infinite number of monkeys to type the collected works of Shakespeare?

Imagine an infinite number of monkeys typing random texts on typewriters. Each monkey has same single unit of typewriter. We assume that typewriters and monkeys are ideal i.e. do not need to be fed/...
223 views

A popular quote from a math rebus

Find the very famous quote from this mathematic rebus. $\sqrt{4b^2} / -2b$
358 views

Series Problem By Gpuzzles - I Have Doubt [duplicate]

gpuzzles.com is one of my favorite sites along with StackExchange, but can someone please elaborate on the answer? Problem: Can you solve the number series problem by replacing boxes with numbers 1, ...
89 views

@Math masti 1234567 [closed]

ā+ā=8 Ć ā Ćā=9 = = ā 5 Solve this plz
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Ten, nine, eight, seven, six, five, four, three, two, one

Some of us already did, and some of us are going to end the years with the word "teen" in it soon, for another 94 years. So let me ask the question: How many distinct numbers can you produce with ...
136 views

The unthinkable sequence

To correctly answer this question, I would like you to include the next 5 numbers of this sequence and also tell me why they are the correct numbers. 3, 4, 8, 9, 14, 23, 25, 31, 36, ?, ?, ?, ?, ? I ...
94 views

Will these two kangaroos meet ever? [closed]

We have two Kangaroos. First one starts from point S1 and jumps for distance D1 in one jump. Second one starts from point S2 and jumps for distance D2 in one jump. Both will jump along the number line,...
147 views

Polygons circumscribed by lines [closed]

You have a plenty of segments of the same length at your disposal. Put a segment and put another to meet at their ends. Set the counterclockwise angle between two segments at 180/5 degrees. If you ...
844 views

Connect 4 Infinite

"Attention everyone! It is the final game of the Connect 4 championship! Billy and Sarah have played perfectly so far during this tournament, so in efforts to prevent Player 1 from being able ...
136 views

Simple Rule Generates this Sequence from Well Known Number Series

First 6 terms generated on applying the simple rule are displayed here. 5, 8, 18, 102, 322, 1830, ?, ?, ? Hint 1: Hint 2: Hint 3:
193 views

Numberless Sudoku with Just a Letter and Symbol Combination

A Standard 9x9 Sudoku uses the digits 1 to 9. You are only allowed to use a single letter(say T) and a symbol of your choice to represent the digits 1 to 9. Rules should be well defined and the ...
269 views

Find the length, width and height of the box [closed]

I have a box. Ratio of length, width and height of the box is $a:b:c$. Ratio of sum of all 12 edges' length, surface area (all 6 sides) and volume is also $a:b:c$ Find the length, width and height of ...
201 views

Get 20160 with 5 2's and any Mathematical Operator [closed]

Here is a mathematical riddle: Find a way to get 20160 with 5 2's and any mathematical operators you want. Have fun! Don't forget that I said any. Feel free to look online for crazy whacky math ...
2k views

Make 82 With Numbers and Dots

How do you make 82 with the numbers $4, 5, 6, 7, 8, 9, 0$ and 8 dots. Get creative! You can use any mathematical operation, and the dots can be used in any mathematical way. No ratios. You must ...
446 views

A Wonderfully Tricky way of Making any Positive Integer [closed]

Make all positive integers, starting from $1$, using: Exactly four $4$'s (and no other digit), concatenation being allowed, Any standard mathematical symbol(s) and operation(s) not listed below. ...
707 views

Resulting number of vampires [closed]

A vampire enters a town and bites 2 person every night. The bitten 2 persons grow into two big vampires and combined bite 4 persons the next night. These 4 vampires combined bite 6 people the next ...
262 views

computer programmer's maths puzzle [closed]

A computer programmer looked at part of his code x = x + 1; and then thought what a strange equation that would be for a mathematician $$x=x+1$$ The programmer ...
152 views

Making 49 from 5, 1, 3, 4 [closed]

I have these numbers: 5, 1, 3, 4. There are four different ways to make 49 - what are they?
853 views

Magic square using consecutive odd numbers -5 through 11

Using consecutive odd numbers from negative five to eleven, make a 3x3 magic square
294 views

The four prisoners [closed]

Four prisoners, 1, 2, 3 and 4, are all condemned to death. One of them is at random selected to be pardoned. 1 asks the guard who will be executed. The guard refuses to tell him so instead 1 says '...
7k views

Magic puzzle of numbers [duplicate]

Send the solution as fast as possible with the way of solving it
97 views

Express 50 to 100 with constituent digits only…my 100th pzl on 50th day

Using the following rules only, Express the numbers from 50 to 100 using only digits in the number. Concise with minimum number of characters is preferred. No concatenation of numbers allowed. Only, ...
110 views

Create numbers from 50-100 only using 1,2,3 and 5 [closed]

Create numbers from 50-100 only using 1,2,3 and 5. No repeats and you have to use each number. Also, you can use any operation! thanks :)?
213 views

A taxi was involved in a hit-and-run accident last night [closed]

A taxi was involved in a hit-and-run accident at night. Two taxi companies, the green and the blue, operate in the city. 85% percent of the taxis are green and 15% are blue. A witness identified the ...
140 views

655 views

How Many Undefined Magic Constants are there?

Magic Square: An nxn square where every horizontal,vertical, and diagonal line all add up to the same number. Magic Constant: The number which every line with a magic square adds up to So most magic ...
64 views

Next number in the following sequence [closed]

1, 2, 3, 5, 8, 13, 21, and so on. Find the next digit.
91 views

In the array of numbers below, each number above the bottom row is equal to three times the number immediately below it. What is the value of x+y? ...
85 views

What is the pattern that describes these numbers? [closed]

Supposed you are given the following numbers: 6 28 496 8128 33550336 8589869056 What's the relation between them?
128 views

Deriving formulae? [closed]

Express 203 as a sum of four terms which are in a Geometric Progression. Then what is the common ratio ? Hence, there by arrive at a common formula for deriving four numbers which are in a G.P. Hint ...
965 views

Squares splitting into 4 congruent shapes [closed]

how many ways can you divide a square into four congruent shapes? Remember that the answer cannot be infinity because rotations of one pattern still result in the same four congruent shapes.
218 views

What number am I thinking of? [closed]

Adding an odd number would make an even number. It's not the largest prime number. But when you divide it into parts I make a multiple of 2. the range never exceeded 100 but never to less from 30. ...
228 views

From the given Square - Factorial Relationship, deduce the unknowns

$Given$: A, B, C, D are distinct digits and can vary from 1 to 9. DB is a concatenated number. From the following relationship, solve for A,B,C,D. Give your deductive reasoning. Please read all ...