Products pass successively through the hands of three traders and each of them sells his goods at a profit of 30% of his cost price. If the last trader sold the products for Rs.300, then how much did the first trader pay for them? 

Find the value of the given expression.

 $$\sqrt { 8+\sqrt { 1681} \ } \ $$

What is the value of $${cos^2A\over {1+sinA}}$$?

Find the cube root of $$ ^{3}\sqrt{-13824}$$.

The measure of a cuboid warehouse is (8 m x 6 m x 3 m). If each sack covers 0.48 cubic meters of space, how many maximum sacks can be kept in it?

25.6% of 250 +√ ? = 119

Find the equation of the line that passing through the point (7, -5 ) and is perpendicular to  the line (4x+5y=1).

If $$ {x+{1\over x}}=2$$ then find out the value of $${2x^2+2}\over{3x^2+5x+3}$$