You report to your supervisor the average length of chain produced per operating hour each week. The equipment operates 5 days a week for 12 hours each day.

According to last week's production numbers shown in the table, how many feet of chain were produced per operating hour?

[tex]
\[
\begin{tabular}{|l|l|l|l|l|l|}
\hline
\text{DAY} & \text{Monday} & \text{Tuesday} & \text{Wednesday} & \text{Thursday} & \text{Friday} \\
\hline
\text{Feet of Chain} & 862 & 905 & 792 & 825 & 816 \\
\hline
\end{tabular}
\]
[/tex]

A. 35
B. 60
C. 70
D. 350
E. 840

First, we find the total number of feet produced during the week by adding the production for each day:

[tex]$$
862 + 905 + 792 + 825 + 816 = 4200 \text{ feet}
$$[/tex]

Next, we determine the total number of operating hours. Since the equipment runs for 12 hours per day over 5 days, the total is:

[tex]$$
5 \times 12 = 60 \text{ hours}
$$[/tex]

Now, to find the average feet of chain produced per operating hour, we divide the total feet by the total hours:

[tex]$$
\frac{4200 \text{ feet}}{60 \text{ hours}} = 70 \text{ feet/hour}
$$[/tex]

Thus, the average is [tex]$\boxed{70}$[/tex] feet per operating hour.