New posts in Problem Solving

probability of guessing a k-digit number sequentially from n trials

Hard problems solving tricks

Given a finite number of stones. We place every stone on an integer. Prove that, given different movements, we can only make finite number of moves

Let $a = \frac{1 + \sqrt{2009}}{2}$ . Find the value of $(a^3 - 503a - 500)^5$ .

If $m,n\in N$ Prove that there is such a positive integer k, such that $(\sqrt{m}+\sqrt{m+1})^n=\sqrt{k}+\sqrt{k+1}$

A square appears randomly within a square of ten time its area. What is probability that the smaller square contains the larger square's center?

The difference between the HCF and LCM of $x$ and $18$ is $120$. Find $x$.

Calculating the number of integers divisible by 8

If $m$ and $n$ are reversed numbers (like $123$ and $321$) and $m * n = 1446921630$ , find $(m+n)$.

Number of possible states on a $6\times 6$ grid