Rate Units – Items paid per 100 cubic metres (% cu m) For which of the following items is the rate commonly quoted per 100 m^3 (also written as per “% cu m”)?
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AEarthwork in excavation
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BRock cutting
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CExcavation in trenches for foundations
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DEarthwork in filling the plinth
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EAll of the above
Answer
Correct Answer: All of the above
Explanation
Introduction / Context:In schedule of rates and bills of quantities, certain bulk earthwork operations are priced per 100 m^3 (commonly denoted “% cu m”) to standardize large-volume tasks and simplify tendering.
Given Data / Assumptions:
- Bulk earthwork items across excavation, trenching, rock cutting, and filling.
- Measurement in cubic metres.
- Conventional rate quotation practices.
Concept / Approach:Items involving large volumes and similar handling are grouped under the per-100-m^3 convention. This includes general excavation, trench excavation (measured in m^3 by section method), rock cutting, and earth filling in plinths.
Step-by-Step Solution:Identify all earthwork-like items in the list.Confirm that each is measured in m^3.Confirm that per-100-m^3 rate convention is applicable to all.
Verification / Alternative check:Standard schedules (e.g., PWD/SOR) show “per 100 m^3” entries for bulk excavation, rock cutting (by volume), and earth filling items.
Why Other Options Are Wrong:
- Options a–d are each correct on their own; hence “All of the above” is the best choice.
Common Pitfalls:Confusing “per m^3” with “per 100 m^3” or assuming trench excavation is always per running metre; in estimation it is typically volumetric unless specifically stated otherwise.
Final Answer:All of the above