What is the value of x $$ {0.081\over x}={0.09\over10}$$ ?

The value of $${\sqrt{40+\sqrt{9\sqrt{81}}} }$$ is

If 12x – 15 y =9x + 5y, the value of $$ {x^{2}+{y^{2}}\over{x^{2}-y^{2}}}$$ is

What is the value of X ?, if 7580 - X = 3440

If 3x + 7y=75, 5x- 5y= 25, then the value of (x +y)=?

The simplified value of
$${{1\over 3}÷{1\over 3}×{1\over 3}\over{1\over 3}÷{1\over 3}of{1\over 3}}-{1\over 9}$$

What will be the total number of pieces if the length of  the rib is cut to 3/4 m length?