Therefore,

We know that ,all the numbers from \[7\]to $17$are:

$7,8,9,10,11,12,13,14,15,16,17$

Whereas n is the total number,

$N=11$

Then,

$\bar{x}=(x1+x2+…xn)/n$

$\bar{x}=(7+8+9+10+11+12+13+14+15+16+17)/11$

$\bar{x}=132/11$

$\bar{x}=12$

Hence, its mean of all numbers from $7$ to $17$ is $12$