Moment of Inertia (M.I.) of four bodies having same mass $M$ and radius $2R$ are as follows\\
$I_1 =$ M.I. of solid sphere about its diameter\\
$I_2 =$ M.I. of solid cylinder about its axis\\
$I_3 =$ M.I. of solid circular disc about its diameter\\
$I_4 =$ M.I. of thin circular ring about its diameter\\
If $2I_2 + I_3 + I_4 = xI_1$ then the value of $x$ will be $\_\_\_\_$.