Question

The average age of five persons in a group is 18 years. The group has an additional

member, such that the new average is 25 years less than the age of the new member.

What is the age(in years) of the new member?​

Answer 1

Answer:

ANSWER

Let the ages of five persons be A,B,C,D and E.

⇒ Total age of A,B and C=84×3=252

⇒ Total age of A,B,C and D=80×4=320

⇒ Age of D=320−252=68

∴ Age of E=68+3=71

⇒ Total age of B,C,D and E=79×4=316

⇒ (A+B+C+D)−(B+C+D+E)=320−316

∴ A−E=4

⇒ A−71=4 [ E=71 ]

∴ A=75