Answer:
The mean speed of the automobiles traveling on this road is the closest to 64 miles per hour
Step-by-step explanation:
Given
[tex]\begin{array}{cc}{Speed} & {Frequency} & {45-55} & {50} & {55-65} & {325} & {65-75} & {275} & {75-85} & {25} \ \end{array}[/tex]
Required
Calculate the mean
First, calculate the midpoint (x)
For 45 - 55: [tex]x = \frac{1}{2}(45+55) = 50[/tex]
For 55 - 65: [tex]x = \frac{1}{2}(55+65) = 60[/tex]
For 65 - 75: [tex]x = \frac{1}{2}(65+75) = 70[/tex]
For 75 - 95: [tex]x = \frac{1}{2}(75+85) = 80[/tex]
So, we have:
[tex]\begin{array}{ccc}{Speed} & {Frequency} & {x} & {45-55} & {50} & {50} & {55-65} & {325} & {60} & {65-75} & {275} &{70} & {75-85} & {25} &{80}\ \end{array}[/tex]
The mean is then calculated as:
[tex]\bar x = \frac{\sum fx}{\sum f}[/tex]
[tex]\bar x = \frac{50*50+325*60+275*70+25*80}{50+325+275+25}[/tex]
[tex]\bar x = \frac{43250}{675}[/tex]
[tex]\bar x = 64.07[/tex]
[tex]\bar x = 64[/tex] --- approximated