$(\sqrt{3}+2)^{2} = \dots$

Prove that one of any three consecutive positive integers must be divisible by $3$.

$A$ sweet seller has $420$ Kaju burfis and $130$ Badam burfis. He wants to stack them in such a way that each stack carries the same number of items and they take up the least area of the tray. What is the maximum number of burfis that can be placed in each stack for this purpose?

For some integer $m$,every even integer is of the form

Prove that one and only one out of every three consecutive positive integers is divisible by $3$.

Express $7429$ as a product of primes.