Question

An automobile mileage and gasoline-consumption testing, 13 automobiles were road tested for 300 miles in both city and highway driving conditions. The following data were recorded for miles-per-gallon performance.

City: 20.3 20.8 20 18.5 17.3 19.4 20.9 20.1 20.2 19.4 19.3 19.4 20.3
Highway: 23.8 25 22.7 23 23.6 21.8 21.6 23 23.4 25.5 23.8 22.9 23.1
Calculate the mean, median, and mode for City and Highway gasoline consumption (to 1 decimal).

Answer 1

For city

Mean = 19.7

Median = 20

Mode = 19.4

For highway

Mean = 23.3

Median = 23.1

Mode = 23.8 and 23

Explanation:

Given:

Data:

City: 20.3 20.8 20 18.5 17.3 19.4 20.9 20.1 20.2 19.4 19.3 19.4 20.3

Highway: 23.8 25 22.7 23 23.6 21.8 21.6 23 23.4 25.5 23.8 22.9 23.1

Now,

For city

Number of terms = 13

Mean =
`\frac{\textup{Sum of all the observations}}{\textup{Total number of observations}}`

Mean =
`(20.3 + 20.8 + 20 + 18.5 + 17.3 + 19.4 + 20.9 + 20.1 + 20.2 + 19.4 + 19.3 + 19.4 + 20.3)/(13)`

or

Mean = 19.68 ≈ 19.7

The median is the middle number in a sorted list of numbers in acceding order

17.3 18.5 19.3 19.4 19.4 19.4 20 20.1 20.2 20.3 20.3 20.8 20.9

Median = 20

Mode = The mode of a set of data is the value in the set that occurs most often

Mode = 19.4 [as it occurs 3 times]

for Highway

Number of observations = 13

Mean =
`(23.8 + 25 + 22.7 + 23 + 23.6 + 21.8 + 21.6 + 23 + 23.4 + 25.5 + 23.8 + 22.9 + 23.1)/(13)`

or

Mean = 23.32 ≈ 23.3

For median arranging the data in ascending order

21.6 21.8 22.7 22.9 23 23 23.1 23.4 23.6 23.8 23.8 25 25.5

Median = 23.1

Mode = Since both 23.8 and 23 occur 2 times, the modes are 23.8 and 23