If the annual income of A, B and C are in the ratio 1 : 3 : 7 and the total annual income of A and C is Rs. 800000, then the monthly salary of B (in Rs. ) is = ?

Explanation:-

	A	:	B	:	C
Annual Income	1	:	3	:	7
Let	x	:	3x	:	7x

Given A + C ⇒ x + 7x = 8x
⇒ 8x = 800000
⇒ x = 100000
⇒ Annual salary of B = 3x
⇒ 3 × 100000 = 300000 $$\eqalign{ & \therefore {\text{Monthly salary}} \cr & {\text{ = }}\frac{{300000}}{{12}} \cr & = {\text{Rs}}.\,25000 \cr}$$