Exercise 11⋅ 1
- If the sides of two squares be a and b metres respectively, what will be the
ratio of their areas?
- If the area of a circle is equal to the area of a square, find the ratio of their
paremetre.
- If the ratio of two numbers is 3 : 4 and their L.C.M. is 180, find the two
numbers.
- The ratio of absent and present students of a day in your class is found to be
1:4. Express the number in percentage of absent students in terms of total
students.
- A thing is bought and sold at the loss of 28%. Find the ratio of buying and
selling cost.
- Sum of the ages of father and son is 70 years. 7 years ago, the ratio of their
ages were 5 : 2. What will the ratio of their ages be after 5 years.
- If a:b b:c, prove that,
(i) 2 2
2 2
b c
a b
c
a
(ii)^222333333
1 1 1
b c
a b c
abc ̧ a
¹
·
̈
©
§
(iii) 1
( )
( )
3
3
ab bc ca
abca b c
(iv)
c
b c
a
a b
a b c
( )^2 ( )^2
2
- Solve : (i)
3
1
1 1
1 1
x
x
(ii) b
a x a x
a x a x
(iii) 2 2 , 2 0 and 0.
2 2
!! z
a b x
x
b
a x a x
a x a x
(iv) 5
1 6
1 6
x x
x x
(v) c
ax b ax b
ax b ax b
(vi)
x
x
x
x
̧
¹
̈ ·
©
§
1
1
1
1
81
3
- If
d
c
b
a
, show that,(i) 2 2
2 2
2 2
2 2
c cd d
c cd d
a ab b
a ab b
(ii) 2 2
2 2
c d
c d
ac bd
ac bd
- If
d
c
c
b
b
a
, show that,
