**I. Find the compound ratio of the following ratios.**

(i) 2 : 3 and 5 : 12

(ii) m : n and n : p

(iii) (a−b): (a+b),(a−b)^{2}: (a+b)^{2}

**Solution:
**(i) Given that,

2 : 3 and 5 : 12

Compound ratio of 2 : 3 and 5 : 12 is

=2*5:3*12

=10:36

=5:18

(ii) Given that,

m : n and n : p

Compound ratio of m : n and n : p

=m*n:n*p

=mn/np

=m/p

(iii) Given that,

(a−b): (a+b),(a−b)

^{2}: (a+b)

^{2 }Compound ratio will be

=(a-b)(a−b)

^{2}: (a+b)(a+b)

^{2 }=(a-b)3:(a+b)3

**II.**Find the compound ratio of each of the following three ratios.

(i) 1 : 2, 4 : 7 and 7 : 8

(ii) a: b, b: c, and c : d

(iii) 2x : 3y, ab : y2 and y : b

**Solution:**

(i) Given that,

1: 2, 4: 7, and 7: 8