A room measures 25 ft * 15 ft * 12 ft. What is the whitewashing cost for the four walls at Rs. 5 per sq ft, accounting for a 6 ft * 3 ft door and three 4 ft * 3 ft windows?
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Answer: D. Rs. 4530
Explanation
Calculating total wall area involves multiplying room perimeter by height to get nine hundred sixty square feet. Subtracting the area of the door and three windows leaves a net surface area of nine hundred six square feet. Multiplying the net whitewashing area by the cost per square foot yields forty five thirty rupees. Room surface area calculations sum the individual wall dimensions while excluding openings like doors and windows. Perimeter of a rectangular room equals two times the sum of length and breadth. Total painting or whitewashing cost equals net surface area multiplied by unit labor rate.
Interior decorators and painters calculate exact wall dimensions to estimate material and labor costs accurately. Construction estimating requires subtracting architectural openings from gross surface area measurements. Understanding spatial dimensions helps homeowners budget for home renovation and maintenance projects. Option A suggests forty eight hundred rupees which fails to subtract door and window areas. Option B suggests thirty six hundred rupees which underestimates the gross room wall dimensions. Option C suggests thirty five sixty rupees which results from subtraction errors during area calculations.
- Subject
- Mathematics
- Category
- Mathematics
- Topic
- —
- Difficulty
- medium
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