Wouldn't it be 1/18x?????
Assume that a step to the north is in the positive direction and a step in the south is in the negative direction.
Then,

and

After 1 hour of independent steps,

and

Therefore, by Central Limit Theorem, the distribution of the random walk is normal with a mean of 0 cm and a standard deviation of 17.32 cm. He is expected to be somewhere around his starting point after 1 hour.
Answer:
13
Step-by-step explanation:
f(10)=10/2+8
f(10)=5+8
f(10)=13