Relation between Mean of Deviations and Mean

Q. The price of different items ordered for a birthday party is given. Find the mean deviation of the data.

1. 40.45
2. 17.45
3. 38
4. 27.45

Q. The number of students in grade 4 to grade 8 in a school is listed. The mean deviation of the data is

1. 4
2. 6
3. 7.2