NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 6: Mensuration - Problems and Solutions
Question 38

Question. 38

In the above question, how many square metres of cloth is required to cover all the display boards? What will be the length in m of the cloth used, if its breadth is 120 cm?

Answer:

Cloth required = 36 m²; Length of cloth = 30 m

Detailed Answer with Explanation:

Step 1: Find total cloth area needed.
Area of one display board = (1.5 ext{m}^2).
Number of boards = (24).
Total area = (24 imes 1.5 ext{m}^2).

Compute it in parts:
(1.5 imes 20 = 30)
(1.5 imes 4 = 6)
So, (30 + 6 = 36 ext{m}^2).

Cloth required to cover all boards = (36 ext{m}^2).

Step 2: Convert the breadth of cloth to metres.
Given breadth = (120 ext{cm}).
(120 ext{cm} = dfrac{120}{100} ext{m} = 1.2 ext{m}).

Step 3: Use the area formula to find the length of cloth.
For a rectangle: ( ext{Area} = ext{Length} imes ext{Breadth}).
So, ( ext{Length} = dfrac{ ext{Area}}{ ext{Breadth}}).

Substitute values:
( ext{Length} = dfrac{36}{1.2} ext{m}).

Divide neatly by removing the decimal:
(dfrac{36}{1.2} = dfrac{360}{12} = 30 ext{m}).

Final Answer:
Cloth required = (36 ext{m}^2).
Length of the cloth (breadth (= 1.2 ext{m})) = (30 ext{m}).

NCERT Exemplar Solutions Class 6 – Mathematics – Unit 6: Mensuration – Problems and Solutions | Detailed Answers