A basement slab pour covers a 25-foot by 18-foot rectangle at 4 inches thick. About how many cubic yards are needed before waste?
Correct Answer
A) 5.56 cubic yards.
Four inches is 0.333 feet. The volume is 25 x 18 x 0.333 = 149.85 cubic feet, and 149.85 / 27 = about 5.56 cubic yards.
Why This Is the Correct Answer
Four inches is 0.333 feet. The volume is 25 x 18 x 0.333 = 149.85 cubic feet, and 149.85 / 27 = about 5.56 cubic yards.
Why the Other Options Are Wrong
Option B: 4.17 cubic yards.
4.17 cubic yards. is below the supported result for concrete takeoff; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 6.25 cubic yards.
6.25 cubic yards. is above the supported result for concrete takeoff; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 8.33 cubic yards.
8.33 cubic yards. is above the supported result for concrete takeoff; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Estimating Garage takeoff: count the condition before counting the package.
Reference Hint
Study anchor (closed-book): memorize Concrete takeoff from CSLB B General Building Study Guide; California Building Code, Title. / Title 24 California Building Code concrete quantity concepts; know the rule or calculation trigger without relying on exam-room lookup.
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