NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 6: Mensuration - True or False Questions
Question 18

Question. 18

An engineer who plans to build a compound wall on all sides of a house must find the area of the compound.

Answer:

false

Detailed Answer with Explanation:

Why the statement is false

To build a boundary (compound) wall around a house, the engineer needs the total length around the house. This is called the perimeter, not the area.

Step 1: Understand the two words

  • Perimeter = total distance around a shape (the boundary length).
  • Area = space covered inside the shape (the surface inside the boundary).

Step 2: Why perimeter is needed for a wall

A wall is built along the boundary. So we need how long that boundary is. That is the perimeter.

Step 3: Quick example (rectangular plot)

Suppose the house plot is a rectangle with length (L = 30, ext{m}) and breadth (B = 20, ext{m}).

Perimeter formula:

[ ext{Perimeter} = 2(L + B) ]

Substitute values:

[ ext{Perimeter} = 2(30 + 20) = 2 imes 50 = 100, ext{m} ]

Area formula (not needed for the wall, just to see the difference):

[ ext{Area} = L imes B = 30 imes 20 = 600, ext{m}^2 ]

Conclusion

For boundary wall construction, we use perimeter, not area. Therefore, the statement is false.

NCERT Exemplar Solutions Class 6 – Mathematics – Unit 6: Mensuration – True or False Questions | Detailed Answers