Solve the following equation 24 + 4 ÷ 4

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

$$3\sqrt{ {72.9\over0.4096}}$$ is equal to : 

Direction : What value should come in the place of question mark (?) in the following questions?

80% of 10% of 340 = ?

The value of $${\sqrt{40+\sqrt{9\sqrt{81}}} }$$ is

The sum of the squares of two positive integers is 100 and the difference of their squares is 28. The sum of the numbers is: 

(0.04)^-1.5 on simplification gives: 

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