The price of one eraser is Rs. 3. The value of 20 eraser is equal to the value of three Pens. The value of one pen is equal to the value of two pencils and the value of six pencils is equal to the value of five markers. What is the value of one marker?

The price of 80 apples is equal to that of 120 oranges. The price of 60 apples and 75 oranges together is Rs. 1320. The Total price of 25 apples and 40 oranges is:

Simplify  $$ ^{3}\sqrt{-2197} × ^{3}\sqrt{{-125}} \ ÷ ^{3}\sqrt{27\over512}$$.

If $${4x^2={15^2-9^2}}$$ then the value of x is

If $$ a={{\sqrt{3}+\sqrt{2}}\over {\sqrt{3}-\sqrt{2}}}$$ and $$ b={{\sqrt{3}-\sqrt{2}}\over {\sqrt{3}+\sqrt{2}}}$$, then find the value  of $$ {a^2\over b}+{b^2\over a}=?$$

If $${a+b=10}$$ and $$ \sqrt{a\over b}-13=-\sqrt{b\over a}-11$$, then what is the value of $${3ab+4a^2+5b^2}$$?

If $$ {3\sqrt{{1-a}\over{a}}}+9={19-3\sqrt{{a}\over{1-a}}}$$, then what is the value of a?

By what least number should 4320 be multiplied so as to obtain a number which is perfect cube?