QUESTIONS AND ANSWERS ON AREA AND VOLUME

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Area: Area represent the amount of space bounded by a border on a flat            surface (2D).
Volume : It represent the amount of space occupied by a 3 dimensional (3D)
                figure.

Q. Find the area of a square of side x cm.
Ans. The area of the square of x cm is x2 cm 2
Q. Find the are of a rectangle of length x cm and width y cm.
Ans. The area of the rectangle of length of x cm and width y cm is xy cm 2
Q. The height of a cone is 30 cm and the area of its base is 154 cm2. Find the volume of that cone.
Ans.  We know that,
              Volume of cone = (1/3) × 𝝿 × (radius of the base)2 × height
                                        = (1/3) × base area × height
Here, the area of the base of the cone is 154 cm2
and the height of the cone is 30 cm
Therefore, the area the cone = (1/3) × 154 × 30 cm3
                                               =1540 cm3
Q. If the breadth of rectangle is (3/5) cm and its area is 1 cm2, what will be its 
    length ?
Ans. We know that,
                  the area of the rectangle = length × breadth
         Here, the breadth is (3/5) cm
                    the area of the rectangle is 1 cm2
By the problem,
                             length ×(3/5) = 1
                        or, length= 1÷(3/5)
                        or, length= (5/3)
∴ The length of the rectangle is (5/3) cm.

Q. Find the area of the ABCD.

Ans.  We know that,
               the area of the trapezium = (1/2) × (sum of the parallel sides) ×
                                                            (distance between them)
Here ABCD is a trapezium.
Therefore, the area of ABCD =(1/2) × (5.8 +3) × 2.3 cm2
                                               = 10.12cm2

 

Know about Triangle  
                                    

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