NCERT Solutions Class 6 Maths Chapter 8 — Perimeter & Area

Solution:

Step 1: Perimeter is defined as the total distance around the outside edge of a two-dimensional shape.

Step 2: Option A describes area, Option C describes angles, and Option D describes a radius for a circle, not a general perimeter definition.

Solution:

Step 1: The formula for the perimeter of a square is 4 × side.

Step 2: Ravi calculated 7 cm × 7 cm, which is the formula for the area of a square (side × side). So, he used the wrong formula.

Step 3: Also, perimeter is a length, so its unit should be 'cm', not 'cm²'. 'cm²' is the unit for area.

Step 4: Therefore, both using the wrong formula and using the wrong unit are mistakes.

Solution:

Step 1: To fence the field, we need to find its perimeter.

Step 2: The formula for the perimeter of a rectangle is P = 2 × (length + breadth).

Step 3: Given length = 12 m and breadth = 8 m.

Step 4: P = 2 × (12 m + 8 m) = 2 × (20 m) = 40 meters.

Solution:

Step 1: Area is the measure of the two-dimensional space a shape occupies.

Step 2: Option A describes units for perimeter or length. Option C is incorrect; area and perimeter are different concepts and usually have different numerical values and units. Option D describes perimeter.

Solution:

Step 1: To find out how much space the garden covers, we need to calculate its area.

Step 2: The formula for the area of a square is Area = side × side.

Step 3: Given side length = 9 meters.

Step 4: Area = 9 m × 9 m = 81 square meters (or 81 m²).