estimate the cost of roofing a building if the roof is 4200 sq ft. The shingles will cost $46.00 per square feet and the labor charge is $38.00 per square. 1 square of shingle covers 100 square feet.
Please verify your statement of the problem:
4200 sq ft * $46 / sq ft = $193,200
1 square of shingle(s) covers 100 sq ft,
so the job requires 4200 sq ft / 100 sq ft = 42 square of shingle(s)
The labor cost would be $38 * 42 = $1,596
As stated, the job would be $193,200 + $1,596 = $194,796
Note: roofing is quoted PER SQUARE, not per sq ft
Material at $46 per square * 42 squares = $1,932
Labor at $38 per square * 42 squares = $1,428
$1,932 + $1,428 = $3,360
Take your pick. One is absurdly high, the other is absurdly low.