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)

{(540.34)/(17.99)} ÷ {(29.99)/(449.89)} × {1/(89.78)} = ?

What should come in place of the question mark (?) in the following mathematical statement?
$${{?^6÷16=108}}$$

If p = 99, then value of p(p² + 3p + 3) is

$$ if \ {1\over x}+x=4,$$ then find $${1\over x^2}+x^2$$

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)

1728 ÷ ? + 149.98 × 25.15 = 3156 - 269.75

$$ {4\over 7}×{2{4\over 5}} ÷{2\over 5}=?$$

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)

? × 350.01 ÷ 3.992² = 983 ÷ 14.001