Page 248 - ICSE Math 7

7. A red carpet 12 m long and 1.5 m wide is kept
for welcoming foreign dignitaries and heads
of state. A 10 cm wide border runs parallel to
the lengths on both the edges. Along the width 1.5 m
of one edge the border is 25 cm wide and on
the other side the border is 0.5 m broad with
‘WELCOME’ inscripted on it. Find the total 12 m
area of the border.

THINK SMART

9 cm

7 cm P Q
1. Calculate the area of regions marked P, Q and R in the
given rectangle.
Area R
25 cm 2

2. Find the area of the shaded portion in the following figures. Are these areas equal? Why?

14 cm 14 cm 14 cm

24 cm 24 cm 24 cm
(a) (b) (c)

3. The area of a triangle is equal to that of a square whose each side measures 70 cm. Find the base
of the triangle in metres, corresponding to the altitude measuring 35 cm.

Maths Lab Activity

I: Area of a parallelogram
A D

Step 1: Draw a parallelogram ABCD on a sheet of coloured
paper and cut it using a pair of scissors.
B C

A D
Step 2: Draw a perpendicular from vertex A to meet BC II
at E. Let the perpendicular divide the figure into I Altitude
two regions I and II.
B E Base C

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