New posts in arithmetic

How to Compare two multiplications without multiplying?

Show that a generalized knight can return to its original position only after an even number of moves

combinatorics geometry arithmetic

How can I easily double any size number in my head?

soft-question arithmetic mental-arithmetic

Is sum of digits of $3^{1000}$ divisible by $7$?

elementary-number-theory modular-arithmetic arithmetic divisibility decimal-expansion

Chinese Remainder theorem with non-pairwise coprime moduli

abstract-algebra number-theory arithmetic

What is to geometric mean as integration is to arithmetic mean?

integration arithmetic average products

How to get the aspect ratio of an image?

Small integral representation as $x^2-2y^2$ in Pell's equation

arithmetic algebraic-number-theory quadratic-forms pell-type-equations

'Bee flying between two trains' problem

How to prove that all odd powers of two add one are multiples of three

elementary-number-theory arithmetic divisibility

6/2*(1+2) is 1 or 9? [duplicate]

arithmetic math-software

Is there a law that you can add or multiply to both sides of an equation?

algebra-precalculus logic arithmetic

Property of 111,111

algebra-precalculus elementary-number-theory arithmetic

Bad Fraction Reduction That Actually Works

elementary-number-theory arithmetic fractions fake-proofs

cubic root of negative numbers

arithmetic wolfram-alpha

How to round 0.4999... ? Is it 0 or 1?

Could the sum of an even number of distinct positive odd numbers be divisible by each of the odd numbers?

number-theory arithmetic recreational-mathematics problem-solving

What exactly IS a square root?

arithmetic exponentiation radicals

Is it wrong to tell children that $1/0 =$ NaN is incorrect, and should be $∞$?

terminology arithmetic indeterminate-forms

Is it possible to simulate a floor() function with elementary arithmetic?