no idea if this is what you're looking for but if it is then here's the answer:
Part 1) The mean is 151
Part 2) The mean absolute deviation is 9.1
Explanation:
step 1
Find the mean
Sum all the values and divide by the number of values
step 2
Determine the absolute value of subtract the mean from each value
step 3
Find the mean of those distances
----> this number is called the mean absolute deviation (MAD)V