How To Solve Problem on Ages Questions Quickly

How To Solve Ages Questions Quickly

Important things to remember on How To Solve Ages Questions Quickly are given below:

  • Decide which age – either it is present or past or future.
  • After deciding the age, Consider it as X.
  • In most cases, we take the present age as ‘X’, i.e., the base year works just fine.
  • Past will express as (x-5) years.
  • The future can be expressed as (x+5).
  • But sometimes, ‘present age’ is not directly given in words. Then, take ‘x’ to be the age you are going to find.
  •  Sometimes when nothing works then just look at the options and solve it through back calculations! It also works fine.
how to solve problems on ages quickly

How To Solve Problem on Ages Questions Quickly

Question 1.

 A boy asks his father, ” what is the age of grandfather?”. Father replied ” He is x years old in x^{2} years”, and also said, “we are talking about the 20th century”. what is the year of birth of grandfather?

A) 1995
B) 1892
C) 1895
D) 1893

Correct Option (B)


20th century means 1900 to 2000

as He is x years old in x^{2} years

only square year in the 20th century is 44^{2}=1936

so Grandfather is 44 years old in 1936
& year of birth of grandfather is =1936-44=1892.

Question 2.

Seven years ago, the combined ages of Amir and Akshay was twice that of Saif. If the sum of the ages of Akshay and Amir, fifteen years hence, is 98 years, what is the present age of Saif?

A) 27 yrs
B) 35 yrs
C) 34 yrs
D) 49 yr

Correct Option (C)


Amir — M

Akshay ..K

Saif .. S

(M -7)+(K-7) =2(S-7)

M + K – 14 = 2S – 14

M + K  = 2S

M+K+30= 98


S= \frac{68}{2} \ =34 yrs.

How To Solve Quickly Questions on Ages

Question 3.

Fathers age is 5 times his son’s age. 4 years back the father was 9 times older than son. Find the fathers’ present age.

A) 36 yrs
B) 40 yrs
C) 50 yrs
D) 43 yrs

Correct Option (B)


let son age=xfathers age=5x

4 years back, so (x-4)=(5x-4)

then father was 9 times older than son so, 9(x-4)=(5x-4)…..(1)

solving eqn (1), x=8

and fathers age =8*5=40 years

Question 4.

In a shopping mall with a staff of 5 members, the average age is 45 years. After 5 years a person joined them and the average age is again 45 years. What is the age of 6th person?

A) 35
B) 23
C) 20
D) 21

Correct Option(C)


The Average age of 5 person after 5 yrs will be 50 yrs.

so total age of 5 person = 50*5=250

and total age of 6 person = 45*6=270

so age of 6th person= 270-250= 20 yrs

Question 5.

Persons standing in the queue with different age group, after two years their average age will be 43 and the seventh person joined with them. hence the current average age has become 45. find the age of the seventh person?

A) 69
B) 70
C) 40
D) 45

Correct Option (A)


Let the age of 6 persons is ‘x’


solution:after two years age will be =(x+12)

average age=43

therefore \frac{x+12}{6} \ =43 \implies x = 246

(x+7th person age)/7= (246+7th person age)/7=45(average age)

(by solving) the 7th person age is 69

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2 comments on “How To Solve Problem on Ages Questions Quickly”

  • sai

    In the 2nd question it was given that seven years ago but, the expression was taken as M+K =2S which should be M+K-14=2S. The correct answer is 27.

    • Prasad

      it correct because 14 will be cancel by solving equation. in M+K+30=98 they just following data mentioned in question