$(21.98)^{2} - (25.02)^{2} + (13.03)^{2} = ?$

Find a number,one-seventh of which exceeds its eleventh part by $100$.

Three-fourths of one-fifth of a number is $60$. The number is:

$\frac{4}{3}$ of a certain number is $64$. Half of that number is

If $2 \frac{1}{2}$ is added to a number and the sum is multiplied by $4 \frac{1}{2}$,and $3$ is added to the product,and then dividing the sum by $1 \frac{1}{5}$,the quotient becomes $25$. What is the number?

$92^{2} - 12^{2} = 3535 + ?$