If the sum of {a\over b}and its reciprocal is 1 and a ≠ 0, b ≠ 0, then the value of a³ + b³ is

Direction: What approximate value will come in place of the question mark (?) in the following question? (You are not expected to calculate the exact value)

6400.002 × 49.99 %   ÷ 999.99 =?

$$\left({?-0.5\over 0.2} \right)={120\over 2}$$

What is the value of $${{0.6}÷{0.6}×{0.6}+{0.5}×{0.5}÷{0.5}\over{0.6}×{0.5}+{0.3}}$$ ?

Simplified form of $$ [(^5\sqrt{x^{-3\over 5}}\ )^{-5\over3}]^{-5}$$

If a³ – b³ – c³ – 3abc = 0, then 

Direction: What approximate value will come in place of the question mark (?) in the following question? (You are not expected to calculate the exact value)

(1110.02 + 89.81) ÷ ? – $${\sqrt{15}}$$= 15.98

If a + b + c = 2, a² + b² + c² = 26 then the value of a³ + b³ + c³ – 3abc is