Example 1:
Find the compounded ratio of
a) 5:14 and 7:15b) a+b:a-b; (a2-b2):(a2+b2) and a2+b2:(a+b)2
Suggested answer:
a) The compounded ratio of 5:14 and 7:15 is
b)The compounded ratio of a+b:a-b; a2-b2:a2+b2 and a2+b2:(a+b)2 is (a+b) (a2-b2) (a2+b2) : (a-b) (a2+b2) (a+b)2
(a+b) (a+b) (a-b) : (a-b) (a+b) (a+b)1:1
Example 2:
If x:y=3:4 find value of (4x+3y) : (2x+5y).
Suggested answer:


Example 3:
If 2x - y : 3x - 2y = 3:4, find x:y.
Suggested answer:

8x-4y=9x-6y
6y-4y=9x-8x2y=x
x:y=2:1
Example 4:
In the ratio 7:8, if the consequent is 40, what is the antecedent?
Suggested answer:

x=35
Antecedent=35.Example 5:
If a:b = 5:8. Find the value of a2b+ab2:a3+b3.
Suggested answer:




Example 6:
Find
a) reciprocal ratio of 3:5b) duplicate ratio of 2:3
c) triplicate ratio of 3:4d) sub duplicate ratio of 25:16
e) sub triplicate ratio of 27:8Suggested answer:
a) Reciprocal ratio of 3:5
b) Duplicate ratio of 2:3
=22:32=4:9c) Triplicate ratio of 3:4
= 33:43= 27:64
d) Sub duplicate ratio of 25:16
e) Sub triplicate ratio of 27:8
= 3:2
Example 7:
If a:b=4:5, b:c=6:7, find a:c and a:b:c.
Suggested answer:


{a:b = 4:5} x 6
{b:c = 6:7} x 5a:b = 24:30
b:c = 30:35 (To make b equal in both ratio)Hence a:b:c = 24:30:35
Example 8:

Suggested answer:

12a+18 = 25a-190
25a-12a = 18+19013a = 208
a = 16
Example 9:
Two numbers are in the ratio 3:4. If 8 is added to the numbers, the ratio becomes 5:6. Find the numbers.
Suggested answer:

6x+48 = 5y+40

y = 16

Example 10:
Divide Rs.256 in the ratio 7:9.
Suggested answer:
Let x be common to the ratio 7:9.
7x, 9x7x+9x=256
16x=256
and 9 x 16 = Rs.144.
