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Title: Question 8
Post by: LisaS on March 14, 2009, 11:54:49 AM

QUESTION 8
Calculate the amount of material required to fill a trench having the following dimensions:
  125 m long × 0.725 m wide with a depth of 0.720 m at the top end of the trench
and 1.735 m at the bottom
Your answer should include an allowance of 34% for compaction.
(Show ALL working.)
Formula: Volume = Length × Width × average depth
           
           
           
           
           
           
           
           
           
           
(5 marks)
Total 5 marks

Title: Re: Question 8
Post by: Plumber on March 26, 2009, 10:36:26 AM

First calculate average depth: (0.720 + 1.735 / 2 ) = 1.2275 (rounded up) = 1.23

125 m long x 0.725 m wide x 1.23 average depth = 111.47 m³

111.47³ + 34% (111.47³ x 0.34) =  37.90³ (for compaction)

37.90³ + 111.47³ = 149.37 m³