Find the mean of the data summarized in the given frequency distribution. compare the computed mean to the actual mean of 47.3 miles per hour.

If we compare this value with the 47.3 proposed we have the following error

The computed mean is close to the actual mean because the difference between the means is less than 5%.  

Step-by-step explanation:

Assuming the following dataset:

Speed   42-45  46-49  50-53  54-57  58-61

Freq.         21        15        6           4          2

And we are interested in find the mean, since we have grouped data the formula for the mean is given by:

And is useful construct a table like this one:

Speed     Freq    Midpoint   Freq*Midpoint

42-45       21            43.5       913.5

46-49       15            47.5        712.5

50-53       6             51.5         309

54-57        4            55.5         222

58-61        2             59.5        119

Total       48                           2276

And the mean is given by:

If we compare this value with the 47.3 proposed we have the following error

The computed mean is close to the actual mean because the difference between the means is less than 5%.  

3.76%

step-by-step explanation:

john earns $14.00 for two hours of work.