The average age of Seeta and Geeta is 40 years. If Reena replaces Seeta, then the average age will become 38 years and if Reena replaces Geeta, then the average age will become 42 yearrs. What are the respective ages of Seeta, geeta and Reena?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 44 years, 36 years and 40 years
The average age of Seeta and Geeta:
(Seeta’s age (S) + Geeta’s age (G))/2 = 40
⇒ S + G = 80 .................(1)
The average age when Reena replaces Seeta:
(Reena’s age (R) + Geeta’s age (G))/2 = 38
⇒ R + G = 76 .................(2)
The average age when Reena replaces Geeta:
(Seeta’s age (S) + Reena’s age (E))/2 = 42
⇒ S + R = 84 ..................(3)
Subtract Equation (2) from Equation (1):
⇒ (S + G) − (R + G) = 80 − 76
⇒ S − R = 4 .............(4)
Now, adding (3) and (4) we get,
⇒ 2S = 88
⇒ S = 88/2 = 44
Now
⇒ R = 84 - S = 84 - 44 = 40
⇒ G = 76 - R = 76 - 40 = 36
SO age of Seeta, Geeta and Reena is 44, 36 and 40 respectively