A concrete housekeeping pad is 6 feet by 4 feet by 6 inches thick. How many cubic feet of concrete are needed before waste?
Correct Answer
A) 12 cubic feet.
Six inches is one-half foot. The volume is 6 feet times 4 feet times 0.5 foot, or 12 cubic feet.
Why This Is the Correct Answer
Six inches is one-half foot. The volume is 6 feet times 4 feet times 0.5 foot, or 12 cubic feet.
Why the Other Options Are Wrong
Option B: 24 cubic feet.
24 cubic feet. is above the supported result for concrete quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option C: 36 cubic feet.
36 cubic feet. is above the supported result for concrete quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 72 cubic feet.
72 cubic feet. is above the supported result for concrete quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Estimating Mechanical takeoff: count the condition before counting the package.
Reference Hint
Study anchor (closed-book): memorize Concrete quantity calculation from 2025 California Building Code, California Code of Regulations Title 24 / Title 24 California Building Code concrete pads and equipment support; know the rule or calculation trigger without relying on exam-room lookup.
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