A school building of 15 classrooms is to be constructed and the cost of construction of the school in terms of per classroom is ₹1,50,000. Calculate the approximate cost of the proposed school building.
- A₹30,00,000
- B₹22,50,000Correct
- C₹20,00,000
- D₹42,50,000
Solution
Concept
In the service unit method, approximate cost = number of service units × cost per unit.
Formula
Cost = N × Cunit
Step-by-step solution
1. Service unit = one classroom. 2. Number of units N = 15. 3. Cost per unit = ₹1,50,000. 4. Total cost = 15 × 1,50,000 = ₹22,50,000.
Explanation
For buildings like schools, hospitals and hostels, a quick estimate is made using the cost per service unit. Here the unit is one classroom. Multiply 15 classrooms by ₹1,50,000 to get ₹22,50,000.
Why the other options are wrong
A: ₹30,00,000 is 20 classrooms, not 15. C: ₹20,00,000 does not equal 15 × 1,50,000. D: ₹42,50,000 is far above the correct product.
Shortcut
15 × 1.5 lakh = 22.5 lakh.
Common mistake
Mixing up lakh and thousand places in Indian number format.
Correct answer: B) ₹22,50,000