A and B are friends and their ages differ by 2 years. A's father D is twice as old as A and B is twice as old as his sister C. The age of D and C differ by 40 years. Find the age of A. A और B दो मित्र है और उनकी आयु का अन्तर 2 वर्ष है। A के पिता D, A की आयु का दुगना है और B अपनी बहन C की आयु का दुगुना है । D और C की आयु का अन्तर 40 वर्ष है । A की आयु ज्ञात कीजिए।

Let A's age = a, then B = a+2 (or a-2). D = 2a (given). Let C = c, then B = 2c (given). D and C differ by 40: 2a - c = 40. If B = a+2 = 2c, then c = (a+2)/2. Substituting: 2a - (a+2)/2 = 40, giving (4a-a-2)/2 = 40, so 3a-2=80, 3a=82 (no integer solution). If B = a-2 = 2c, then c = (a-2)/2. Substituting: 2a - (a-2)/2 = 40, giving (4a-a+2)/2 = 40, so 3a+2=80, 3a=78, a=26. Check: A=26, B=24, D=52, C=12, D-C=40. Option A works.