Page 188 - Ganit Kaushal

III. State whether the following statements are True (T) or False (F).

1. The cost of levelling a rectangular ground at `1.25 per sq m. is `900. If the length of the ground is
30 metres, then the width is 24 cm.

2. The length of a rectangle is three times its breadth. The perimeter of the rectangle is 48 cm. The area
2
of the rectangle is 105 cm .
2
3. If the perimeter of a square is 16 cm, then the area of the square is 16 cm .
4. If the area of a square A is 16 times that of a square B, then the perimeter of A is 4 times the perimeter
of B.
5. If the length of a rectangle is halved while the breadth is tripled, the change in area is half of itself.

IV. Solve the following questions.
1. Find the number of marble slabs of size 20 cm × 30 cm required to pave the floor of a square room
of side 3 m.

2. A 5 m wide lawn is cultivated all along the outside of a rectangular plot measuring 90 m × 40 m. Find
the total area of the lawn.
3. Around a rectangular garden of length 10 m and width 5 m, a road 1 m wide is laid. Find the cost of
2
laying the road at `200 per m .
4. Find the number of square-shaped tin sheets of side 20 cm that can be cut off from a square tin sheet
of side 1 m.

5. The cost of levelling a rectangular ground at `1.25 per sq. metre is `900. If the length of the ground
is 30 metres, find the width of the ground.
2
6. If the perimeter of a rectangular field is 200 m and its breadth is 40 m, find its area (in m ).
7. The cost of fencing a square garden is `400 at the rate of `1 per metre. Find the area of the garden in
square metres.
8. Find the shaded area by counting the squares (i.e., by using conventions C1-C4).

(a) (b) (c)
9. Find the greatest and the least possible perimeters of a rectangle of area 49 sq cm.

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