Part 1)
we have
the scale is 
the distance on a map is 
we know that
The scale is equal to the distance on a map divided by the real distance
Let
x------> distance on a map
y-------> real distance
S-------> scale

In this part we have

Find the value of y

Substitute the values


Convert to kilometers

Part 2)
In this part we have

Find the value of x

Substitute the values


Convert to centimeters

therefore
the answer is
The distance is 
There are four values, including the unknown value x. The sum of the four values is the given value of the mean, 11.5, multiplied by four. Let S be the sum of the four values. Then we can write:


x = 46 + 5 = 51
The answer is: The value of x is 51.