$${a\over b}={2\over3}$$ and $${b\over c}={4\over5}$$ then the ratio  $${a+b}\over {b+c}$$ equal to:

If $$ {P={96\over95×97}},{Q={97\over96×98}}$$ and $$ {R={1\over97}}$$ then which of the following is True?

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

If $$ {x+{1\over {x}}=1}$$, then find the value of $$ {x^{208}+{x^{205}+x^{204}+x^{201}}}$$.

If a+b = 1 and a³+b³+3ab=k, then the value of k is : 

If $$ {3x+}{2\over {\sqrt{x}}}=1$$ then $$ {x-{\sqrt{x}}}=?$$

If a+b=17,and a – b =9, then the value of $$ {(4a^2+4b^2)}$$ is:

(x+2y) (x² + 4y² – 2xy) equal to-