Since the mean of the two numbers x and y is:

\(\frac{x+y}{2}\) = 4

 x+y =2 * 4

x+y = 8

then we get:

\(\frac{x+2x+y+2y}{4}\)

=(\(\frac{3x+3y}{4}\))

= 3(\(\frac{x+y}{4}\)) → 3(\(\frac{8}{4}\)) 

= 3 * 2

= 6