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\ 06-Jan-2025 Bharat Arora Proof-7 Reader’s Sign _______________________ Date __________

Chapter assessment
A. Choose the correct option.

1. The area of a rhombus if the lengths of its diagonals are 6 cm and 4 cm respectively is
(a) 36 cm 2 (b) 12 cm 2 (c) 24 cm 2 (d) 13 cm 2

2. A cube of side 5 cm is painted with colours on all its faces. It is sliced into 1 cubic centimetre cubes.
How many 1 cubic centimetre cubes will have exactly one of their faces painted?
(a) 27 (b) 42 (c) 54 (d) 142

3. A cube of side 4 cm is cut into 1 cm cubes. What is the ratio of the surface areas of the original cubes
and cut-out cubes?
(a) 1 : 2 (b) 1 : 3 (c) 1 : 4 (d) 1 : 6

4. What will be the change in the volume of a cube when its side becomes 10 times the original side?
(a) 1000 times of original volume (b) 10 times of original volume
1
(c) 100 times of original volume (d) times of original volume
1000
5. Raman has three containers: Cylindrical container A having radius r and height h, cylindrical
1
container B having radius 2r and height h, and cuboidal container C having dimensions r × r × h.
2
The arrangement of the containers in the increasing order of their volumes is
(a) A, B, C (b) B, C, A (c) C, A, B (d) cannot be arranged

6. The surface areas of the six faces of a rectangular solid are 16, 16, 32, 32, 72, and 72 sq. cm. The
volume of the solid, in cubic centimetres, is

(a) 192 (b) 384 (c) 480 (d) 2592

B. Assertion and Reason type Questions.
In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R).
Choose the correct option.
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.

(d) Assertion (A) is false but Reason (R) is true.
1. Assertion (A): The area of the largest triangle that can be fitted into a rectangle of length l units and
breadth b units is lb sq. units.
2
Reason (R): Area of a triangle = 1 × Area of a rectangle
2
2
2. Assertion (A): If the area of the face of a cube is 9 cm , then the total surface area of the cube is
2
54 cm .
Reason (R): The total surface area of a cube is six times the area of one of its faces.

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