If $$ {\sqrt{1+{473\over{256}}}=1+{x\over 16}}$$ then what does x equal to ?

What is the value of $${0.74×1.23×0.13\over (0.37)^{3}+(0.41)^{3}-8(0.39)^{3}}$$ ?

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

The value of $$ \sqrt{11.981+7\sqrt{1.2996}}$$ is closest to 

Simplify : $$ {(7) ^{2} ÷(7^{1\over 2})^{4}}$$

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

Simplify the following equation
$$ {\sqrt{(1-sin^{2}θ) ÷{(1-cos^{2}θ)}}}$$

If the average of 11, 23 and x is 40, then what is the value of x?