The ratio among A, B, C and D = 1/3 : 1 / 4 : 1/5 : 1/6
On rearranging the ratio = 60/3 : 60/4: 60/5 : 60/6 = 20 : 15 : 12 : 10
So minimum number of pens can be when the common ration is 1.

Correct Option: C

The ratio among A, B, C and D = 1/3 : 1 / 4 : 1/5 : 1/6
On rearranging the ratio = 60/3 : 60/4: 60/5 : 60/6 = 20 : 15 : 12 : 10
So minimum number of pens can be when the common ration is 1.
So minimum number of pen = 20 + 15 + 12 + 10 = 57

If three parts be P, Q and R,
then, P/2 = Q/3 = R/5
⇒ P : Q : R = 2 : 3 : 5

Correct Option: B

If three parts be P, Q and R,
then, P/2 = Q/3 = R/5
⇒ P : Q : R = 2 : 3 : 5
∴ P = (2/10) x 990 = 198
Q = (3/10) x 990 = 297 and
R = (5/10) x 990 = 495

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