The highway speeds of 100 cars are summarized in the frequency distribution below. Find the mean speed. Speed (MPH) Cars 30-39 5

Question

2 years ago

14

40-49 18 50-59 50 60-69 17 70-79 10

1 answer:

Alexus [3.1K] · Answer 1 · 2023-05-17T03:05:23+03:00

The mean speed of the 100 cars is 55.4

<h3>How to determine the mean?</h3>

The table of values is given as:

Speed (MPH) Cars

30-39 5

40-49 18

50-59 50

60-69 17

70-79 10

Rewrite the frequency table to include the class midpoints

x f

34.5 5

44.5 18

54.5 50

64.5 17

74.5 10

The mean speed is then calculated as:

$\bar x =\frac{\sum fx}{\sum f}$

So, we have:

$\bar x = \frac{34.5 * 5 + 44.5 * 18 + 54.5 * 50 + 64.5 * 17 + 74.5 * 10}{100}$

Evaluate

$\bar x = 55.4$

Hence, the mean speed is 55.4