Simplify the following expression.
12 + 2.5 + (1.5 of 4) - 2.6

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

If a³ – b³ – c³ – 3abc = 0, then 

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

$$ {40 \%}\ of( {20\over 4}×?)=48$$

The value of $$5-{8+2\sqrt{15} \over4}-{{1}\over8+2\sqrt{15}}$$ is equal to:

If p – 2q = 4, then the value of p³ – 8q³ – 24pq – 64 is :

If x = 222, y = 223 and z = 224, then find the value of x³+y³+z³-3xyz