The city mileage (in miles per gallon) for 24 family sedans

Mileage (in miles per gallon)                        Frequency

22 – 27 ………………………………………….      16

28 –33 ………………………………………….        2

34 – 39………………………………………….         2

40 – 45 ………………………………………….       3

46 – 51 ………………………………………….       1

Approximate the mean of the frequency distribution.