5. Solution:
Ratio of the breadth and length = 3:5
Then, breadth = 3x
length = 5x
Perimeter = 24m
2 (l + b) = 24
2(5x + 3x) = 24
10x + 6x = 24
16x = 24
x =
24
16
∴ x =
3
2
so now, breadth = 3x = 3 x
3
2
= 4
1
2
m
length = 5x = 5 x
3
2
= 7
1
2
m
6. QN 2: In a regular polygon,the ratio of the inner and outer angle
is 7:3 .
1.What is each angle ?
2. How many sides does the polygon have?
7. Solution:
1. Let the inner angle be 7x and outer angle be 2x.
Since they form a linear pair .
7x + 2x = 180
9x = 180
x =
𝟏𝟖𝟎
𝟗
∴ x = 20
Inner angle = 7x
= 7 x 20 =𝟏𝟒𝟎 𝟎
Outer angle = 2x
= 2 x 20 =𝟒𝟎 𝟎
8. 2. Sum of outer angle of apolygon of n sides is 𝟑𝟔𝟎 𝟎
It is a regular polygon . The outer angles are equal.
n x 40 = 360
n =
𝟑𝟔𝟎
𝟒𝟎
∴ n = 9
∴ number of sides of the polygon = 9
