Elsewhere these figures were presented as part of an anaolgy but I have some concern about the answer provided.

Here’s the given:

A material is being manufactured at 7 to 10 cubic meters per second, 24 hours a day. At such a rate, if placed on an American football field the material would cover it to a depth of 240 feet per day.

Assuming an American football field (100 yards x 50 yards) is 91.4 by 53.5 or 4890 square meters and 7 x 60 x 60 x 24 / 4890 = 123.7 and 10 x 60 x 60 x 24 / 4890 = 176.7 square meters, wouldn’t the daily field depth converted to square feet (x 10.76) range from 1331 to 1902 feet?

If endzones (10 yards x 50 yards) are included, wouldn’t I just reduce the depth by 20%?

Granted, I suck at math so I appeal to you, the Doper community, for accucy in the hopes that a proper analogy can be drawn. Since the likelihood is that I’m the one who’s wrong I wanted to check the calculation before offering an alternative. Thanks!

Well, you have a small mistake here, but generally you are on the right lines.

You multiplied instead of dividing by the conversion factor here. 50 yards = 45.7m

So, the area of the field is 91.4 x 45.7 = 4180 square metres.

At 7 cubic metres per second, daily output = 7 x 60 x 60 x 24 = 604800 cubic metres.

Divide that by the area: 604800/4180 = 145 metres.

This is equal to (145 x 3.28) = 480 feet.

Given that this is the lowest estimate of the output, and the depth is twice the given figure, yes, someone has screwed up. (Assuming you have the dimensions of a football field right, which I have no idea about!)

The actual width of an NFL field is 53 1/3 yards (160 feet) - cite. It’s a small correction, and doesn’t sound terribly relevant in this situation, since we seem to be dealing in round numbers, anyway. Nevertheless,… FYI