If $50$ is subtracted from two-third of a number,the result is equal to the sum of $40$ and one-fourth of that number. What is the number?

$A$ number consists of two digits such that the digit in the ten's place is less by $2$ than the digit in the unit's place. Three times the number added to $\frac{6}{7}$ times the number obtained by reversing the digits equals $108$. The sum of the digits in the number is:

$250 \%$ of $? \div 250 - 444 = 200$

$\frac{753 \times 753 + 247 \times 247 - 753 \times 247}{753 \times 753 \times 753 + 247 \times 247 \times 247} = ?$

$n$ is a whole number which when divided by $4$ gives the remainder $3$. The remainder when $2n$ is divided by $4$ is

The sum of squares of three consecutive natural numbers is $2030$. What is the middle number?