Question

American-Made Cars: Below is a frequency table for the MPG ratings of 479 different American-Made cars.

American-Made Cars

MPG	Frequency
10 − 14	70
15 − 19	170
20 − 24	159
25 − 29	70
30 − 34	10

(a) The class midpoint for the third class is  .

(b) The class midpoint for the fourth class is  .

(c) Use the frequency table to estimate the mean MPG for all cars in this group. Round your answer to 1 decimal place.

x =

Answer 1

Given table:

MPG	Frequency
10-14	70
15-19	170
20-14	159
25-29	70
30-34	10

a) We have to find mid point for the third class.

Formula:

b) We have to find mid point for the fourth class.

c)

Making a table for better calculation.

MPG	Frequency(f)	Midpoint(x)	xf
10-14	70	12	840
15-19	170	17	2890
20-14	159	22	3498
25-29	70	27	1890
30-34	10	32	320
Total	479		9438

Now,

Done