Page 183 - Start Up Mathematics_5

SCRATCH YOUR BRAIN

1. The length and breadth of a rectangle are 6 cm and 3 cm, respectively. Find the
perimeter of a rectangle formed by joining the width of 3 such rectangles.

2. The length and breadth of a rectangle are 4.5 cm and 2 cm, respectively. If a square
is perfectly attached to the width of the rectangle, what will be the total area of the
new rectangle formed?
3. The length of a square is 8 cm. How many such squares can be arranged to form a
rectangle of length 24 cm and breadth 16 cm.

4. Shreya lives in a rectangular-shaped house that is 75 m long and 50 m wide. She wishes
to plant trees around it to protect its outer walls from direct sunlight. The trees are to
be planted 3 m apart. How many trees will she need so that they surround the house
completely? (Round off your answer to the nearest whole number.)

PAIR ACTIVITY

To find the perimeter and area of different shapes using squared sheet of paper

Things We Need: Squared sheet of paper, a pencil and a ruler
How To Do:

1. Take a squared sheet of paper. Trace the base of your pencil box on it.
2. Also trace the base of your eraser, chalk box of your class and your lunch box.

3. Now find the perimeter and area of these shapes and complete the table given below.

Object Perimeter of base Area of base

Pencil box _________________ _________________
Eraser _________________ _________________

Chalk box _________________ _________________
Lunch box _________________ _________________

Extension:

Take a chocolate bar which has square pieces. Calculate its area by counting the number of
squares in it. Have fun eating it after finding its area.

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