Let the quantity be k.
Then, (a + k) / (b + k) = c/d

Correct Option: D

Let the quantity be k.
Then, (a + k) / (b + k) = c/d
⇒ (a + k)d = (b + k)c
⇒ ad + dk = bc + ck
⇒ ad - bc = ck - dk
⇒ ad - bc = k(c - d)
∴ k = (ad - bc) / (c - d)

Given, A : B = 2 : 3
and B : C = 4 : 5
Then, A : B : C = 8 : 12 : 15
7there4; Share of B = [12/(8 + 12 + 15)] x 7000

Correct Option: C

Given, A : B = 2 : 3
and B : C = 4 : 5
Then, A : B : C = 8 : 12 : 15
7there4; Share of B = [12/(8 + 12 + 15)] x 7000
= (12 x 7000)/35
= 2400
= ₹ 2400

Let A's share = 3N
B's share = 9N
and D's share = 13N
According to the question
7N = 4872
∴ N = 4872/7 = 696
Share of A and C = 3N + 9N = 12N

Correct Option: A

Let A's share = 3N
B's share = 9N
and D's share = 13N
According to the question
7N = 4872
∴ N = 4872/7 = 696
Share of A and C = 3N + 9N = 12N
= 12 x 696 = ₹ 8352

Age of A = (3/8) x 56 = 21 yr
Age of B = (5/8) x 56 = 35 yr

Correct Option: C

Age of A = (3/8) x 56 = 21 yr
Age of B = (5/8) x 56 = 35 yr
Before 7yr, ration of the ages of A and B
= (21 - 7) : (35 - 7)
= 14 : 28
= 1 : 2

Correct Option: B

=		r1		2	×	h1
		r2				h2

=		2		2	×	5
		3				3