If  $$ \ {xy\over x+y}= a, $$ $${xz\over x+z}=b $$ and $$ {yz\over y+z} =c $$  where a, b, c are all non – zero numbers, then x equals to

If  $$n+{2\over 3}n+{1\over2}n+{1\over7}n=97$$ then the value of n is : 

Simplification 

If then the value of

If average of two x and $$1\over x$$ (where x ≠ 0) is A, what will be the average of x³ and $$1\over {x^3}$$?

If $$ x={\sqrt3\over{2}}$$ then the value of $$ \sqrt{1+x}-\sqrt{1-x}$$ will be

If a = 2.234, b = 3.121 and c = –5.355, then the value of $$ a^3 + b^3 + c^3 – 3abc$$ is

If $$64^{x+1}={64\over 4^x}$$, then the value of x