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 Question from Marielena: If the production rate for hand digging a trench is 1.2 mh/cy, how long would it take for one man to dig a trench 2 feet deep by 1 foot wide by 216 feet long?

Hi Marielena,

I don't know what mh is but I expect cy is cubic yards. In any case the volume of material to be removed to form the trench is its width times its depth times its length. You have these measurements in feet so that will give the volume in cubic feet. In your case that's $2 \times 1 \times 216 = 432$ cubic feet. You can use the internet to convert this to cubic yards. Just type What is 432 cubic feet in cubic yards? into the Google search window or ask Google or Siri the same question. Each cubic yard takes 1.2 mh. How long will it take to dig the trench?

Penny

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