A shingle roof estimate requires 10 percent waste on 28 roofing squares. How many total squares should be ordered?
Correct Answer
A) 30.8 squares.
Ten percent waste on 28 squares is 2.8 squares, so the total is 30.8 squares.
Why This Is the Correct Answer
Ten percent waste on 28 squares is 2.8 squares, so the total is 30.8 squares.
Why the Other Options Are Wrong
Option B: 28.8 squares.
28.8 squares. is below the supported result for roofing quantity calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option C: 35 squares.
35 squares. is above the supported result for roofing quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Option D: 38 squares.
38 squares. is above the supported result for roofing quantity calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Measure to percent, adjust for waste, then let Checking Material set the finish line.
Reference Hint
Study anchor (closed-book): memorize Roofing quantity calculation from California Building Code, California Code of Regulations Title 24. / Title 24 California Building Code roof covering quantity concepts; know the rule or calculation trigger without relying on exam-room lookup.
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